136 MEMOIRS OF THE NUTTALL ORNITHOLOGICAL CLUB. 



He states that Scaups are easily decoyed, sometimes alighting on the tri- 

 angular pieces of wood on which the wooden decoys are nailed, and allowing 

 themselves to be pulled in within gunshot. One of the most interesting sights 

 is a large flock or " raft " of these birds, as it is appropriately called, on account 

 of their habit of swimming closely huddled together. They are skillful divers 

 and often remain a long time under water. Their flight is swift and direct, and 

 they frequently turn from one side to the other in flight. 



With the sun full upon them, the adult males show beautiful greenish, 

 iridescent heads and necks, yellow eyes, and pale blue bills. Except under these 

 favorable conditions, the heads and necks appear black, contrasting beautifully 

 both on the water and in flight with the light gray, nearly white backs, and the 

 white sides and bellies. The tail is black. In flight the front third of the body 

 and front of the wings appear black, the posterior two thirds of the body and 

 the secondaries white, the tail alone being dark. The white at the base of the 

 bill in the otherwise inconspicuous brownish females is very noticeable on side 

 view and gives them rather a comical appearance when they are head on to the 

 observer. Their bills appear as blue as those of their mates. 



57 [149] Aythya affinis (Eyt). 



Lesser Scaup; "Little Bluebill." 



Common transient visitor in the autumn, rare in the spring ; March 2 to 

 April 14 ; October 8 to November 27. 



The habits of the Lesser are very similar to those of the Greater Scaup, 

 but the former bird is less commonly found in salt water. 



Full adults have purple reflections on the head and neck instead of greenish 

 as in the larger species, but one needs most favorable light to make this out 

 even with a good glass. As a rule, the heads in both species look black. The 

 females and immature in both the species appear to differ in size only. The 

 majority of adults and young are noticeably smaller than marila but it is some- 

 times very difficult to distinguish immature birds even in the hand. 



