BIRDS OF NORTH AND MIDDLE AMERICA. 289 
PISOBIA COOPERI (Baird). 
COOPER’S SANDPIPER. 
Similar in coloration to P. fuscicollis but summer adult ¢ with 
white of median upper tail-coverts broken by V-shaped marks of 
dusky, and size decidedly greater. 
Adult male in swmmer (sex not determined).—General color of upper 
parts brownish gray or grayish brown, the feathers blackish centrally or 
mesially, producing rather large, irregularly cuneate spots on back and 
scapulars and streaks elsewhere, the latter broadest on crown, where 
the ground color inclines to grayish buff; a few of the more posterior 
scapulars slightly tinged with light cinnamon-buff or rusty ochraceous; 
rump dusky brownish gray, the feathers margined with grayish white 
and with blackish shaft-streaks; upper tail-coverts white, with 
irregular sagittate and V-shaped marks of dusky; wing-coverts 
brownish gray, the smaller with darker centers and blackish shafts, 
the greater distinctly tipped with white; remiges dusky, the proximal 
primaries edged basally with white, the proximal secondaries more 
broadly margined terminally with white; shafts of primaries white 
post-medially, passing into grayish brown basally and terminally; 
tail ight brownish gray, the middle rectrices darker, becoming still 
darker terminally, the others narrowly margined with whitish; sides 
of head and neck white or grayish white, faintly tinged with buffy or 
pale ochraceous and narrowly streaked with dusky, the supraloral 
region, however, nearly immaculate (minutely and sparsely flecked); 
under parts white, the chin, upper throat, breast, abdomen, and anal 
region immaculate, the lower throat, foreneck, and chest tinged with 
buffy and rather densely streaked with dusky, the upper breast, sides, 
and flanks marked with irregular streaks (becoming more or less 
sagittate or hastate on flanks) of dusky, the under tail-coverts 
with narrow mesial streaks of the same; axillars and most of under 
wing-coverts immaculate white, the coverts near edge of wing spotted 
with dusky, the under primary coverts pale gray edged and tipped 
with white; length, about 241.5; wing, 146; tail, 57; exposed culmen, 
31; tarsus, 29; middle toe, 22. 
Long Island, New York (Raynor South, May 24, 1833; only one 
specimen known). 
@ No other phase of plumage is known. 
5 One specimen, the type, No. 5989, coll. U. S. Nat. Mus., Raynor South, Long 
Island, New York, May 24, 1833; collected by William Cooper. 
The relationship of this bird, the type of which remains unique, is distinctly with 
P. fuscicollis, from which it could hardly be distinguished but for its decidedly greater 
size, all its measurements exceeding the maximum of them of P. fuscicollis. It needs 
no comparison with Canutus canutus, the coloration, in toto, and the proportions being 
very different. 
40017—19—Bull. 50, pt 8——20 
