22 



KEY C (Cont.) 



15 Wing entirely black or dark brown, or black or dark brown with 



several white secondaries; unwebbed 4th toe is lobed (Plate 36-3); 

 outer of 3 webbed toes longest; 12-24 tail feathers. 



SEE WATERFOWL (Page 33) 



15' Wing color not as in 15; 4th toe neither webbed nor lobed (Plate 

 35-3); middle of 3 webbed toes longest; 12 tail feathers. 



See GULLS (Page 51) 



KEY D. SIZE SMALL, WING <161 mm 



1 Primaries 10-8 and sometimes 7 cut out on inner, outer or both webs 

 (Fig. 10); 12 primaries; no tail; tarsi flattened laterally (Plate 

 37); viewed from above the outer edge of folded wing curves decidedly 

 outward, away from body (Fig. 18a). See GREBES (Page 25) 



I 1 Primaries not cut out or 10 and 9 only slightly so; 11 primaries 

 (outermost often minute); prominent tail; tarsi rounded in cross 

 section; shape of wing not as above. 2 



2 Body plumage compact, feathers overlapping tightly; viewed from above, 

 partly folded wings stubby and decidedly curved inward along outer 

 edge (Fig. 18c); wings rather broad, the ratio of width to total 

 length is 0.30 - 0.40; three toes webbed, the fourth either lobed 

 (Plate 36-3) or absent (Plate 36-1). 3 



2' Plumage much fluffier, individual feathers overlapping loosely; 

 wings long and slender, ratio of width to total length is 0.22 to 

 0.31; folded wing straight or curved only slightly inward along 

 outer edge; arrangement of toes not as in 2. 5 



3 Wing <138 mm; feet with only 3 toes, all connected by webbing 



(Plate 36-2). See ALCIDS (Page 66) 



3' Wing 138-161 mm. 4 



4 Feet with only 3 toes, all connected by webbing; tarsus 15-31 mm; a 

 maximum of 12 tail feathers. See ALCIDS (Page 66) 



4' Feet with 4 toes, 3 connected by webbing and 4th reduced in size 

 (Plate 36-3); tarsus 30-35 mm; 14-24 tail feathers. 



See WATERFOWL (Page 33) 



