48 



KEY TO SHOREBIRDS (Cont.) 



29 Underwings light and lacking conspicuous dark markings on leading 



edge; bill swollen dorsally near tip; hind toe lacking. 30 



29' Underwings mostly dark or if light then with conspicuous dark 31 

 markings on the leading edge (Fig. 20c). 



30 Wing length 135-160 mm; bill length 18-24 mm; dark shoulder patch 

 absent; tail gray-brown basal ly, dark toward tip. MOUNTAIN PLOVER 



30' Wing 90-115 mm; bill 12-17 mm; shoulder patch present; outer portion 

 of tail whitish with central portion grayish-brown and darker toward 

 tip. SNOWY PLOVER 



31 White on upper surface of outer web of the 5th primary runs from 



the feather margin to shaft (Fig. 21-1,2 and 4). 32 



31' White on upper surface of outer web of the 5th primary does not 35 

 reach shaft (Fig. 21-3). 



32 Wing length 160-190 mm; tail white basal ly, dusky near tip. 



SURFBIRD 



32' Wing <160 mm. 33 



33 Black on outer web of 5th primary meets shaft at obtuse angle 



(Fig. 21-2); toes not lobed. SANDERLING 



33' Black on outer web of 5th primary meets shaft at acute angle 



(Fig. 21-1 ,4); toes lobed. 34 



34 Wing length 100-118 mm; bill tapering gradually toward sharp tip 



(Plate 21-3). NORTHERN PHALAROPE 



34' Wing 120-140 mm; bill swells noticeably laterally near tip before 

 tapering to a point (Plate 21-2). 



RED PHALAROPE 



35 Wing length 145-180 mm; secondaries all dark; tail pale brownish- 

 gray, not conspicuously darker centrally. RED KNOT 



35' Wing <145 mm. 36 



