DUCKS, SWANS AND GEESE. 



225 



Food. — Small crustacean (Artemia salina) in Camargue (W. E. 

 Clarke) ; grasses and water-plants growing beneath surface in 

 Spain (A. Chapman) ; only vegetable matter in stomach (Salvin) ; 

 univalve mollusca (Cerithia) (R. Wagner) ; bivalve mollusca 

 (Radde). 



Distribution. — England and Wales. — Very rare vagrant. Obtained 

 some fifteen times, but some were certainly escaped birds, and most 

 recorded in recent years are open to that suspicion. 



Distribution. — Abroad. — From basin of Mediterranean (Spain, 

 south France) to west Siberia, Lake Baikal and Persian Gulf, 

 Africa and India to Ceylon, but apparently not breeding in tropics, 

 excepting on Cape Verde Islands, a group inhabited by a number 

 of other Palaearctic forms. Casual Canaries. 



Order A N S E R E S . 



Containing the Ducks, Swans and Geese, also Mergus. Also 



called Anseriformes. Bill is 

 sufficient to distinguish them 

 from all other European birds ; 

 it is covered by thin skin, has at 

 tip a horny plate shaped like a 

 finger-nail and termed a " nail " ; 

 edges of mandibles with rows of 

 fine lamellae. Skull desmogna- 

 thous, holorhine. Basi-pterygoid 

 process much in front. Syrinx 

 in most species (except Oidemia) 

 widening into a horny sac 

 (^ drum "), which differs in the 

 various species. Tarsus in Cygnus 

 and Anser entirely reticulated but 

 in Ducks with a row of scutes 

 along front. Toes always 4, hind- 

 toe higher than front toes, which 

 are connected by full webs. 

 Primaries 11, first reduced, small, 

 stiff Aftershafts rudimentary or 

 absent. Under feathers a rich 

 covering of down. Eggs un- 

 spotted. 



Popular division into Ducks, 

 Geese and Swans cannot be main- 

 Tarsus of a. The Grey Lag-Goose, b. The tained and therefore only one 



Mallard, to illustrate reticulated tarsus of -F Qrn il-rr onnpntprl 

 Swans and Geese and partially scutellated iclIllil 3 <w^epteu. 

 tarsus of Ducks. 



VOL. II. 



