40 
BIRDS OF PENNSYLVANIA. 
visitor in Pennsylvania. This species is one of the first to arrive in 
spring, being seen here often early in March frequenting principally the 
rivers and other larger streams. 
Genus AIX Boie. 
Aix sponsa (Linn.). 
Wood Duck ; Summer Duck ; Acorn Duck. 
Description ( Plate 4 ). 
Bill high at base and shorter than head, the latter crested. 
Male Adult. —Head with conspicuous green and purple crest; sides of head irides¬ 
cent purple, streak of white from base of bill to occiput, streak back of eye contin¬ 
uous with that of throat pure white ; sides and front of lower neck and fore part of j 
breast bright-chestnut with fine white spots; lower parts generally white; upper 1 
surface of wings beautifully marked with iridescent metallic hues. Female with 
grayish head and lengthened feathers behind ; throat white ; fore neck, upper breast 
and sides brownish-yellow, and streaked with grayish ; upper parts generally dark- 
brown glossed with purple chiefly. Length about 19 inches ; extent about 28 inches. 
Habitat.— Temperate North America, breeding throughout its range. 
The Wood Duck is a resident, and breeds in various sections of this 
commonwealth. During the breeding season it generally is found about 
streams and ponds in heavily wooded and thinly populated districts. 
In Pennsylvania this species is rare in winter and most plentiful in 
autumn. The Wood Duck is an abundant winter resident in Florida, 
where it also breeds. I have seen downy young of this bird which were 
captured late in March, 1885, in Orange county, Florida. “ The Wood 
Duck breeds in the Middle states about the beginning of April, in Mas¬ 
sachusetts a month later, and in Nova Scotia, or on our northern lakes, 
seldom before the first days of June. In Louisiana and Kentucky, 
where I have had better opportunities of studying their habits in this 
respect, they generally pair about the first of March, sometimes a fort¬ 
night earlier. I never knew one of these birds to form a nest on the 
ground or on the branches of a tree. They appear at all times to pre¬ 
fer the hollow, broken portion of some large branch, the hole of our 
large Woodpecker, or the deserted retreat of the fox squirrel; and I 
have frequently been surprised to see them go in and out of a hole of 
any one of these, when their bodies, while on the wing, seemed to be 
nearly half as large again as the aperture within which they had de¬ 
posited their eggs. Once only I found a nest (with ten eggs) in the 
fissure of a rock, on the Kentucky river, a few miles below Frankfort. 
Generally, however, the holes to which they betake themselves are either 
over deep swamps, above cane-brakes, or on broken branches of high 
sycamores, seldom more than forty or fifty feet from the water. They 
are much attached to their breeding places, and for three successive 
years I found a pair near Henderson, in Kentucky, with the eggs, in the 
beginning of April, in the abandoned nest of the Ivory-billed Wood- 
