xviii SYSTEMATIC ARRANGEMENT OF THE GENERA OF BIRDS 



ORDER ANSERES 



Tarsus about length of femur, reticulate at back and generally in front 

 Bill straight, always with distinct nail at tip of upper mandible. Young 

 covered with down, and able to run or swim in a few hours after hatching. 



, FAMILY ANATID^ 



(Ducks, Geese, Swans, etc.) 



Bill thick, broad, high at the base, covered with a thin membranous skin 

 and ending in a nail-like horny tip ; edges of the mandibles cut into thin 

 parallel ridges, or toothed ; wings moderate ; legs placed not very far be- 

 hind ; . feet, four-toed, palmated ; hind toe free, placed high on the tarsus. 

 Food, grass and aquatic weeds, worms, insects, molluscs, and small fish. 



SUB-FAMILY ANSERINE 



77. Anser (Geese). Bill nearly long as head, elevated and covered with 



cere or skin at base ; conspicuous nail at tip ; under mandible 

 smaller than upper ; nostrils lateral, near middle of bill ; tail of 

 sixteen feathers ; legs under centre of body ; hind toe free, articu- 

 lated upon tarsus. Page 176 



78. Bernicla (Brent and Bernicle Geese). Bill shorter than head, higher 



than broad at base ; culmen slightly convex, outline of lower man- 

 dible decidedly so, leaving elliptical space displaying lamella? ; 

 nostrils sub-basal ; neck feathers less furrowed than in A nser ; tail 

 short, rounded ; tibia feathered to joint ; hind toe short and ele- 

 vated. Page i3o 



79. Cygnus (Swans). Bill of equal length throughout, furnished with 



knob at base ; nostrils medial ; legs short ; neck exceedingly long. 



Page 181 

 SUB-FAMILY A NAT I DAI 



Bill of equal width throughout, or broader at the top than at the base, of 

 about the same width as the head ; legs short, placed rather behind the middle 

 of the body ; hind toe without a pendent membrane ; tarsi somewhat round. 



80. Tadorna (Sheldrake). Bill with an elevated tubercle at the base, 



depressed in the middle; nostrils large, pervious; lower portion 

 of tarsus in front with a row of transverse scutella?. Page 184 



81. Anas (Mallard, Gadwall). Bill long as head, broad, depressed, sides 



parallel, sometimes partially dilated, both mandibles with transverse 

 lamellae on inner edges ; nostrils small, oval, lateral, anterior to 

 base of bill ; wings rather long, pointed ; tail wedge-shaped ; legs 

 rather short ; hind toe without lobe. Sexes differ in plumage. 



Page 185 



82. Spatula (Shoveller). Bill much longer than head, widening towards 



end, lamella? projecting conspicuously ; no soft membrane on sides 

 of bill towards tip; wing pointed, first and second quills longest; 

 tail short, graduated; legs very short. Page 189 



83. Dafila (Pintail). Bill long as head, edges nearly parallel, widening a 



little to end, lamella? 'not strongly defined ; neck long, slender ; tail 

 sharply pointed, central rectrices considerably elongated in male; 

 margin of web to anterior toes slightly emarginate. Page 190 



84. Querquedula (Teal). Bill long as head, lamella? exposed along pro- 



jecting edge of upper mandible ; tail of sixteen feathers, short and 

 rounded; hind toe very small, outer shorter than third, centre 

 rather long ; inter digital membrane emarginate. Page 191 



