SCAUP-DUCK, OR BLACK-HEAD. 299 



DESCRIPTION. 



The length of the Blue-Bill is nineteen inches; extent twenty- 

 nine inches; bill broad, generally of a light blue, sometimes of 

 a dusky lead color; irides reddish; head tumid, covered with 

 plumage of a dark glossy green, extending half-way down the 

 neck; rest of the neck and breast black, spreading round to the 

 back; back and scapulars white, thickly crossed with waving 

 lines of black ; lesser coverts dusky, powdered with veins of 

 whitish; primaries and tertials brownish black; secondaries 

 white, tipped with black, forming the speculum ; rump and tail 

 coverts black; tail short, rounded, and of a dusky brown; 

 belly white, crossed near the vent with waving lines of ash ; 

 vent black ; legs and feet dark slate. 



