8 Geese of Europe and Asia 



or also brown nail (young birds). On belly of adults a greater 

 or less number of transverse brown or black patches (some- 

 times confluent or even covering greater part of belly). Genus Anser, Brisson (1760). 



11 (12) Length of culmen not less than 60 mm. ( = 2.36 in.); rump and 

 margin of wing pale ashen grey. Legs flesh or roseate with- 

 out orange tint. Culmen 1 61-72 mm. ( = 2.40-2.83 in.) ; wing 

 400-500 mm. ( = 15.70-19.60 in.). A. anser, Linnaeus. 



12(11) Culmen less than 60 mm. ( = 2.36 in.) 2 ; rump dark slaty brown ; 

 legs orange or yellow, rarely with roseate tinge ; edge of wing 

 dark brownish grey. Around base of upper mandible lies a 

 broad white band (adult) or narrow black margin, in which are 

 sometimes scattered separate white featherlets (young birds). 



13 (14) Culmen not less than 40 mm. (=1.57 in.). When bill is shut, 



almost all teeth of upper mandible visible from without. 

 Around eye absence of well-marked yellow ring, formed by 

 ceroma. In adult, white spot on forehead does not go farther 

 back than line joining anterior angles of eyes, while usually 

 falling far short of the same. 

 Culmen 40-56 mm. (=1.57-2.20 in.); wing 375-435 mm. 

 (=14.70-17.10 in.). Length of nail on upper mandible 

 included more than three times in total length of culmen. A. albifrons, Scopoli. 



14 (13) Culmen less than 38 mm. (= 1.49 in.). When bill is shut, teeth 



of upper mandible not visible from without or noticeable only 

 near gape. 3 Ceroma forms somewhat swollen yellow ring 

 around eyes. In adult, white space projects backward over fore- 

 head considerably beyond line joining anterior angles of eyes, 

 but rarely reaches line joining their posterior angles. 

 Culmen 29-37J mm. (=1.40-1.47 in.); wing 345-395 mm. 

 (=12.60-15.50 in.). Length of nail on upper mandible 

 included three times in total length of culmen. A. finmarchicus, Gunner. 



15 (10) Basal half of upper mandible or parts of it, culmen and nails of 



both mandibles, always black ; light parts of bill yellow (to 

 orange inclusive) or pink to dark flesh or reddish. In young 

 birds, black colouring on bill always prevails over light. 

 Never any black patches on the belly. Genus Melanonyx, Buturlin (1901). 



16 (29) Colouring of light parts of bill and legs identical. 



17 (20) Light parts of bill and leg pink or flesh coloured. 



18 (19) Margin of wing dark grey-brown; culmen 55-63 mm. ( = 2.16- 



2.48 in.) ; wing 450-488 mm. ( = 17.70-19.20 in.). M. neglectus, Sushkin. 



19 (18) Margin of wing bluish ashen grey; culmen 42-48 mm. (1.65- 



1.88 in.); wing about 400 mm. (=15.70 in.) (from lack of 

 material, I cannot give more definite limits for the variation in 

 the length of the wing). M. brachyrhynchus, Baillon. 



20 (17) Ordinarily, light parts on bill and leg yellow or orange-yellow 



1 Sometimes, as stated by undoubted authorities, the bill in this species is also orange-coloured, which in such case must certainly 

 be dependent on a considerable layer of subcutaneous fat, whereof I shall have occasion to speak in greater detail when describing this 

 species. 



2 Personally I have not happened to see an example with a bill longer than 56 mm. (2.20 in.), but among American specimens, 

 distinguished by the name A. albifrons gambeli, bills sometimes occur with culmen reaching 60 mm. (2.36 in.). 



3 However, in dry skins, in which the skin at the edges of the upper mandible has become somewhat raised or warped in the process 

 of drying, the teeth are visible from without, but this is an abnormal phenomenon. 



