248 



LONG-WINGED SWIMMERS - LONGIPENNES. 



f^^ 



Outer primary slate-black, about 2.50 inches of the subterminal portion (including the shaft) 

 wliite, the tip again black ; iimer web more slaty than the outer, the basal half sometimes ashy 

 white, minutely freckled with darker, l)ut usually uniform slaty gray, paler basally ; second quill 

 with the basal half of the outer web and much more of the inner pale bluish gray (much like the 

 mantle), a large space of white, about 1.75 inches in extent, near the end, the intervening space 

 black, abruptly contrasted with the basal pale bluish gray ; a small apical spot of white, preceded 

 by a broad subterminal one of black, about .70 of an inch in length ; third quill tipped with white, 



the subterminal portion Wack for about 1.00 inch 

 on the inner, and more than 2.00 inches on the 

 outer web (next the shaft), the remaining portion 

 pale grayish blue, becoming nearly or quite white 

 on the inner web where adjoining the black ; fourth 

 ([uill similar, but the black more restricted, and 

 the outer web becoming white posteriori}^ ; fifth, 

 similar, but with the black space more restricted, 

 forming a subternuual band about .75 of an inch 

 wide, the white preceding it still more extensive 

 than on the fourth quill ; sixth with a still nar- 

 rower black band (seldom more, generally less, than 

 .50 of an inch wide) ; remaining quills pale pearl- 

 blue, passing gradually, but broadly, into white, 

 terminally, the seventh sometimes with a small 

 black bar near the end of the outer web. Rest of 

 the plumage snow-white. " Bill bluish green, its terminal third bright yellow ; legs and feet 

 dusky bluish green, the webs yellowish" (CouEs).^ Adult, in wmter : Similar, but the head and 

 neck, sometimes also the jugulum, longitudinally spotted with light grayish brown. Nearly adult : 

 Similar, but the white of the primaries more restricted and the black more extended, the latter 

 color more brownish ; quills without white apical spots ; bill more or less dusky terminally ; tail 

 sometimes (in younger individuals) more or less blotched with dusky terminally, and upper tail- 

 coverts sometimes (rarely) faintly barred with grayish brown. Head, etc., spotted or immaculate, 

 according to the season. Young, first plumage : Above, grayish brown, the feathers widely and 

 distinctly bordered with pale grayish buff ; rump and upper tail-coverts grayish buify white, marked 

 more or less distinctly with irregularly sagittate spots of grayish brown ; basal half of the tail 

 grayish white or pale grayish, transversely mottled Avith darker ; terminal portion dusky grayish 

 brown, forming a well-defined broad zone, the tip whitish. Head, neck, and lower parts nearly 

 uniform light brownish gray. Primaries uniform dusky grayish brown, the terminal margin paler. 

 Bill dusky, more brownish at base; feet (in skin) light brown. Older: Similar, but the light 

 borders to the feathers of back, etc., purer white ; basal half of the tail uniform bluish white ; 

 lower parts white, the breast and sides spotted with light grayish l)ro\vn ; liasal half (or less) of the 

 bill light colored. Upper parts more or less tinged with the pale blue of the adult plumage. 



Total length, about 17.50 to 18.00 inches ; extent 43 ; wing, 13.20-14.50 (average, 13.93) ; 

 culmen, 1.25-1.70 (1.45) ; depth of bill, ,40-.50 (.45) ; tarsus, 1.70-2.10 (1.94) ; middle toe, 

 1.30-1.55 (1.44). [Twenty-six adults.] 



This species, while agreeing closely with L. canus in size and general appearance, may be very 

 easily distinguished when adult by the dissimilar pattern of the primaries, and the somewhat 

 diflFereut proportions, as shown in the diagnosis on p. 210. In many specimens (chiefly younger 

 individuals), the dark portion of the primaries is dusky brownish, instead of black. In one (No. 

 70299, St. Michael's, Alaska ; L. M. Turner), a perfectly adult, though probably not a very old, 

 bird, this color is quite a light grayish brown, as though the color had been washed out, the 

 pattern being the same as in most adult specimens. 



1 "Adult, high breeding-plumage : Eyelids, ocular region, and gape of mouth, bright orange-yellow, 

 which color extends over the tij) and cutting edges of the bill ; the green of the bill with a peculiar hoary 

 glaucescence. Legs and feet bluish green, the webs bright gamboge-yellow " (CouEs). 



Adult male (No. 70299, U. S. Nat. Mus., St. Michael's, Alaska, May 31, 1875) : " Iris dark hazel ; 

 bill, feet, and toes dark greenish yellow, webs yellowish ; eyelids crimson" (L. M. Turner, MS.). 



