44 
BIRDS OF PENNSYLVANIA. 
Ay thy a affinis (Eyt.). 
Liesser-Scaup Duck ; Little Black-head. 
Description {Plate 62). 
Very similar to the previously described species, measuring about 16 inches in 
length and about 2§ inches in extent ; head glossed with purplish-violet. 
Habitat . — North America in general, breeding chiefly north of the United States, 
migrating south to Guatemala and the West Indies. 
The Little Black-head or Little Blue-bill, a common spring and fall 
migrant, is found generally throughout the state. At Erie bay it is one 
of the most common ducks, being found tlii^re regularly, when migrat- 
ing, in large flocks. During mild winters small, scattered flocks of this 
species are frequently met with in this region. Dr. Walter Yan Fleet, 
of Benovo, Pa., informs me that about four years ago he saw a pair of 
these ducks for two consecutive seasons, during the summer months, 
inhabiting an extensive marshy meadow in Northumberland county. Pa., 
where he believes they bred. In the winter of 1885 I found the Little- 
Blue-bill in immense flocks at Lake George, Florida, where it is known 
as the Baft Duck. 
Ay thy a collaris (Donov.). 
Ring-necked Duck. 
Description. 
Very similar to Black-head ; male with narrow brownish ring about middle of 
neck ; speculum gray ; back blackish ; head and neck above ring black, glossed with 
green and purplish violet. Female has brownish head and neck, chin, sides of head 
and ring about eye whitish. Bill in male is black, lighter at base and at end, and in 
female is brownish-black ; tarsi, bluish-gray ; eyes yellow. Length about 18 inches ; 
extent about 28 inches. 
Habitat. — North America, breeding far north and migrating south to Guatemala 
and the West Indies. 
The Bing-necked Duck is a regular and reasonably common spring 
and fall migrant in this state. At Erie bay it is often found in company 
with other species, particularly the Little Black-head. The Bing-necked 
Duck feeds largely on seeds of different aquatic plants. 
Genus GLAUCIONETTA Stejneger. 
Glaucionetta clangula americana (Bonap.). 
American Golden-eye ; Whistler. 
Description {Plate 59). 
Bill considerably shorter than head, and very high at base ; frontal feathers ex- 
tend beyond those on sides ; tail of sixteen feathers and rather pointed. 
Male. — Head and upper part of the short neck glossy-green, and a rounded patch 
of white along base of bill in front of eye (in a young male before me the head is 
