210 BULLETIN 50, UNITED STATES NATIONAL MUSEUM. 
groove; nostril sub-basal, longitudinally linear, its upper edge oper- 
culate; anterior outline of feathering at base of bill descending 
obliquely downward and forward in a nearly straight line, from base 
of culmen to lower edge of mandible, the mental antia very slightly 
anterior to this point. Wing rather long, pointed, the longest pri- 
mary (outermost) exceeding distal secondaries by a little more than 
half the length of wing and extending decidedly beyond tips of. 
longest tapering but round-tipped tertials. Tail about two-fifths as 
long as wing, truncate or slightly rounded (E. mauri) or slightly 
emarginate on each side (doubly emarginate), with four middle 
rectrices longest; rectrices 12. Tarsus longer than exposed culmen 
(E. pusillus, male) to decidedly shorter (£. mauri, female), equal to 
one-fourth the length of wing or slightly less, continuously scutellate 
anteriorly and posteriorly; bare portion of tibia shorter than middle 
toe without claw, scutellate before and behind; middle toe with 
claw as long as or very slightly shorter than tarsus in E. pusillus, to 
decidedly shorter (about six-sevenths) as long in E. mauri; lateral 
toes decidedly shorter than middle toe, the outer longer than the 
inner; claws rather long, slender, moderately curved; basal phalanges 
of anterior toes united by web, that between the outer and middle 
toes much larger than that between inner and middle toes. 
Coloration.—Above mostly brownish gray, beneath whitish. In 
summer adult spotted with blackish and more or less tinged or inter- 
mixed with rusty. 
Range.—North America, migrating to South America and West 
Indies. (Two species.) 
KEY TO THE SPECIES OF EREUNETES. 
a. Bill shorter (17-20, averaging 18.6 in male, 18-22, averaging 20.3 in female); 
summer adults with little of rusty on upper parts, the prevailing color above being 
grayish brown; chest narrowly streaked with dusky; young with little of rusty or 
ochraceous on upper parts. (Eastern North America, breeding along Arctic coast 
westward to Point Barrow, Alaska; Middle and South America in migration.) 
Ereunetes pusillus (p. 210). 
oa. Bill longer (20.5-23.5, averaging 22.5 in male, 23-28, averaging 25.9 in female); 
summer adults with upper parts chiefly rusty or cinnamon-rufous, the chest with 
broad streaks or triangular spots of dusky; young with much rusty, and ochraceous 
on upper parts. (Western North America, north to coast of Bering Sea.) 
Ereunetes mauri (p. 215.). 
EREUNETES PUSILLUS (Linnzus). 
SEMIPALMATED SANDPIPER. 
Adults in summer.—Above light grayish brown, or brownish gray, 
the sides of pileum and some of the scapulars and interscapulars 
tinged with pale buffy cinnamon, but this sometimes wholly absent; 
pileum heavily streaked and dorsal region heavily spotted with 
black, the latter occupying the central portion of each feather; rump, 
