DUSKY DUCK. 393 



Many migrate north as well as into the interior at the 

 approach of spring. Their principal food in autumn and 

 winter appears to consist of minute shell-fish, particularly 

 those univalves which are so abundant in the salt marshes. 

 They also at times, in great numbers, visit the sandy beach 

 in quest of small bivalves and other shelly mollusca ; and 

 occasionally feed on seeds of aquatic and bog plants, such 

 as those of the Scheutzeria, and as usual swallow gravel 

 with the rest of their fare. They roost in the shallow ponds 

 and islands where many are caught by the minx and fox ; 

 and are extremely shy during the day, being at that time 

 very seldom seen except when surprised in their retreats, or 

 alarmed by the report of the gun, when they often rise from 

 the marsh in great numbers, and disperse confusedly in 

 every direction. In calm weather they fly high, but when 

 the wind blows hard, they proceed within gun shot over the 

 the salt meadows, and may then be brought down in great 

 numbers by the concealed gunner, as they proceed over 

 their usual track. Their voice or quack resembles that of 

 the common Wild Duck, and their flesh when well fed, 

 notwithstanding the nature of their food, is scarcely inferior 

 to that of any other species. 



The Dusky Duck is about 2 feet in length 5 and 3 feet 2 inches 

 in alar extent. The upper part of the head is deep dusky -brown, 

 with small streaks of drab on the fore part ; the rest of the head and 

 greater part of the neck, dull yellowish-white, each feather marked 

 down the centre with a line of blackish-brown. Inferior part of the 

 neck, and whole lower parts, dusky, the feathers edged more or less 

 broadly with brownish- white ; upper parts the same, but deeper. 

 Speculum blue, with green and amethyst-red reflections. Wings 

 and tail dusky ; the tail feathers sharp pointed. Bill greenish-ash, 

 formed much like that of the Mallard, about 2^ inches long measured 

 from above. The legs and feet dusky-yellow. 



The female is browner ; but in other respects resembles the male, 

 having in common with it the alar speculum. 



