No. 17. 



Aythya marila nearctica. 



Adult male. Head, neck, fore part of breast, and front of 

 back black ; the gloss about head chiefly greenish. Lower part 

 of back, the long wing-feathers, and tail mostly brownish black. 

 Wing-mark, or speculum, white. Middle of back, sides of body, 

 and flanks beautifully pencilled with black and white zigzag 



No IT. Adult Male. 



lines, the same extending on to wings, but less conspicuously. 

 Under surface of body principally white, though pencilled like 

 flanks on lower belly, and blackish beneath tail. Bill broad, and 

 of light bluish lead color with black nail at end. Legs and feet 

 gray, with blackish webs. Eyes yellow. 



