632 BULLETIN 5 0, UNITED STATES NATIONAL MUSEUM 



tween anterior extremities of feathered portion of rami nearly equal 

 to length of gonys, the latter very indistinctly if at all ridged, rather 

 strongly convex, ascending termmally, not promment basally (owing 

 to width of mandibular rami); maxillary tomium with subterminal 

 "tooth" large and very prominent, behind which the tomium is first 

 concave, then convex and again concave; nostril relatively large, 

 broadly oval (with axis vertical) . Wing long and pointed, the longest 

 primaries exceeding distal secondaries by decidedly less than half the 

 length of wnng; second and third primaries longest, the first (outer- 

 most) shorter than fourth; mner web of outermost primary abruptly 

 emarginated about opposite tip of seventh primary (from outside); 

 that of the second less abruptly but distinctly emarginated a little 

 anterior to tip of fifth primary; outer webs of second and thhd pri- 

 maries sinuated. Tail more than half as long as wing, rounded, the 

 graduation about equal to length of bare portion of acrotarsium, the 

 middle pair of rectrices tapering distally and slightly shorter than 

 next pair. Feet very strong, the middle toe, without claw, decidedly 

 shorter than tarsus, the latter with upper half densely feathered (ex- 

 cept a narrow strip on planta tarsi), the bare portion covered with 

 small roundish or hregularly oval scales, these larger and more trans- 

 verse in front, especially on inner side; outer toe (without claw;) ex- 

 tending decidedly beyond penultimate articulation of middle toe, and 

 equal in length with inner toe; hallux nearly as long as combined 

 length of first two phalanges of middle toe and slightly to decidedly 

 longer than its claw. 



Plumage and coloration. — Plumage compact, the feathers rather 

 hard and stiff, especially the primaries and rectrices; orbital region 

 bare, but not extensively so; loral region and cere behind nostril 

 densely clothed with narrow feathers with long bristlelike tips. 

 Adults grayish brown or dusky above, usually mxore-or-less barred or 

 transversely spotted with pale huffy or dull whitish, the posterior 

 portions more broadly and regularly barred and of a more bluish 

 gray cast, the underparts mostly white more or less spotted with 

 grayish brow^n or dusky, the markings longitudinally guttate on 

 chest, in form of bars on flanks, thighs, and under tail coverts. Young 

 grayish brown, the head and neck streaked with whitish (this some- 

 times predominating) the feathers of back, wings, etc., margined with 

 whitish or buft'y; underparts white or huffy white, longitudinally 

 striped with grayish brown. One form nearly uniform dusky grayish 

 brown or sooty, another white with transverse markings of grayish 

 brown or dull slate color in adults and longitudinal markings in young. 



Range. — Chcumpolar regions, migrating southward. (One species 

 with several races.) 



