394 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I50 



8. Black bars on tail and upper tail coverts decidedly broader than white ones. 



Long-billed dowitcher, Linmodrotnus scolopaceus, p. 413 

 Black bars on tail and upper tail coverts not wider than white ones, the 

 latter usually decidedly broader. 



Short-billed dowitcher, Linmodrotnus griseus, p. 410 



9. Primary wing coverts and secondaries with conspicuous white markings. 10 

 Primary coverts and secondaries not broadly and conspicuously white. 12 



10. Bill longer, 30 mm. or more 



Bill straight, rump and upper tail coverts prominently barred with black 

 and white Knot, Calidris canutus rufa, p. 415 



Bill slightly but definitely decurved at the tip, rump and upper tail coverts 

 gray or brownish gray without bars. .Dunlin, Erolia alpina pacifica, p. 424 



Bill shorter, less than 30 mm., lower back or upper tail coverts white. . . 11 



11. Lower back extensively white; tarsi and feet orange to orange-red. 



Ruddy turnstone, Arenaria interpres morinella, p. 408 



Lower back gray to sooty gray, tarsi and feet duller colored, greenish 



yellow Surfbird, Aphriza virgata, p. 407 



12. Tail feathers all, or except central pair, white banded with black 13 



Tail feathers not extensively white barred with black, except for one or 



two of the outer ones in some species 14 



13. Larger ; upper tail coverts white, barred somewhat with sooty black, wing 



more than 145 mm.; tarsus bright yellow. 



Lesser yellowlegs, Totanus fiavipes, p. 399 



Smaller; upper tail coverts dark, wing less than 145 mm., tarsus dark 



olive-green Solitary sandpiper, Tringa solitaria, p. 400 



14. Tail more than 75 mm.; axillars and under surface of outer primaries 



white or whitish, broadly barred with black or grayish black. 



Upland plover, Bartramia longicauda, p. 395 



Tail less than 70 mm., under surface of outer primaries not distinctly and 



evenly barred 15 



15. With a pronounced buffy color, brightest on lower surface. 



Buff-breasted sandpiper, Tryngites suhruficollis, p. 426 



Without evident buff on lower surface, which is white on the abdomen, 



or wholly white 16 



16. Tarsus more than 35 mm.; legs long and slender, with the bare portion 



(crus) above the tarsal joint equal to middle toe without claw. 



Stilt sandpiper, Micropalama himantopus, p. 425 



Tarsus less than 35 mm.; legs proportionately shorter and stockier, with 



the bare portion (crus) above the tarsal joint definitely shorter than 



middle toe without claw 17 



17. Rump and upper tail coverts gray or greenish gray. 



Spotted sandpiper, Actitis macularia, p. 402 

 Rump and upper tail coverts black, sooty, or black and white 18 



18. Larger, wing more than 115 mm 19 



Smaller, wing less than 105 mm 21 



19. Rump white ; tip of maxilla pitted. 



White-rumped sandpiper, Erolia fuscicollis, p. 421 

 Rump black or dusky ; tip of maxilla smooth 20 



