Plate IV. Pages 8G, 88. 
HERRING GULL. 
Length, 24-00 inches. Adult, back and wings pearl-gray; end of primaries 
marked with black; rest of plumage white. Young, dark grayish, primaries 
and tail brownish black. 
PETRELS. 
Length, 7-50 inches. Black, upper tail-coverts white. 
