BIRDS OF ESSEX COUNTY. 1 45 



of this region, the Black Duck, by the fact that they are constantly diving ; but 

 both on the water and in flight, the short necks and large heads of the Scoters 

 together with their chunkier bodies easily distinguish them from the longer, more 

 clipper-built Black Duck whose white wing-lining is always diagnostic. All 

 the Scoters cock their tails up at times in such a way as to suggest Ruddy 

 Ducks. I have watched a White- winged Scoter asleep with its head tucked into 

 the back feathers, and its tail partly spread and cocked up so that the bird looked 

 for all the world like a huge Ruddy Duck. The shorter tail of the Scoter in 

 proportion to the size of the bird should, however, distinguish it. 



The adult male American Scoter is very black, wings and all, and the 

 swollen yellow base of the bill is a conspicuous mark. The female and young 

 have bills of ordinary shape. They are sooty brown above and much lighter, 

 grayish white below. The American Scoter is noticeably smaller than the 

 White-winged Scoter. 



67 [165] Oidemia deglandi Bonap. 

 White-winged Scoter; "White-winged Coot." 



Abundant transient visitor, common in winter ; (summer) ; September 6 to 

 June 4. 



As a few always spend the summer and as I saw as many as thirteen 

 together off Ipswich Beach on July 17th, 1904, it is rather difficult to set the 

 date for autumn arrivals. The habits of this bird have already been given 

 under the American Scoter. 



The White-winged Scoter is easily recognized in flight by its broad white 

 wing-patches. These, however, although they sometimes show, are often invisi- 

 ble when the bird is swimming, whereas in the Red-breasted Merganser and the 

 Whistler these white patches are almost always noticeable. This Scoter is apt to 

 give himself away, however, by standing up in the water and flapping his wings. 

 The adult male is glossy black, with a small white mark under the eye which 

 can be seen at a considerable distance with a good glass. The swollen red and 

 orange bill can also be made out with a glass. The female and immature are 

 sooty brown and show a faint white spot at the base of the bill, and a more dis- 

 tinct one behind the eye. 



