12 
BIRDS OF PENNSYLVANIA. 
taxidermist, mounted one of these birds, which had been shot by a hunter 
in Sullivan county. Pa., near Eagle’s Mere, a popular summer resort on 
the Philadelphia and Reading railroad. 
Btercorarius parasiticus (Linn.). 
Parasitic Jaeger. 
Description. 
Adult ^ — Upper part of the head blackish-brown; nape and sides of the neck 
yellowish-white; remainder of upper plumage blackish-brown; wings and tail 
darker ; shafts of the primaries white ; under plumage white ; bill bluish at the base, 
black at the point ; tarsi and feet black ; the central tail feathers extend beyond the 
others about three inches ; they taper slightly, varying but little in breadth until 
near the end, where they are abruptly acuminated, differing in this particular from 
all the other species. 
Young . — Head and neck streaked with dark brown and brownish-yellow ; lower 
parts spotted or barred with the same; upper parts brownish or dusky and brownish- 
yellow. Length about 18 inches ; extent about 40 inches.” — Baird's Birds of N. A. 
Habitat . — Northern part of northern Hemisphere, southward in winter to South 
Africa and South America. Breeds in high northern districts, and winters from the 
Middle states and California southward to Brazil and Chili. 
The Parasitic Jaeger, like the preceding species, occurs in Pennsylva- 
nia only as a rare and irregular straggler. Dr. Turnbull {Birds of 
Eastern Pennsylvania) records the capture of one near Philadelphia by 
the late John Krider. In October, 1874, Mr. Merrick Low shot, at the 
head of Erie bay, a fine specimen of this bird, which is now in the col- 
lection of my friend, Mr. George B. Sennett, of Erie city. Dr. Walter 
Yan Eleet mentions both the Pomarine and Parasitic Jaegers as strag- 
glers in Clinton county. Pa. 
Never having had an opportunity of studying this species in life, I 
quote the following interesting extracts from Mr. E. W. Nelson’s report 
{Natural History Collections in Alaska) : “ During summer these Jaegers 
show a much greater preference for marshes- and the low, barren 
grounds so common in the north, than they do for the vicinity of the sea- 
coast. At the Yukon mouth, and near St. Michaels, they arrive with the 
first open water, from the 10th to the 15th of May. The snow still lies 
in heavy drifts on most of the open country, but the Jaegers take pos- 
session and feed upon the shrew-mice and lemmings which are common 
on this ground. By the last of May they are very common, and twenty 
or thirty may be seen in a day’s hunt. 
“ Birds in the black plumage are rare in the spring, but are sometimes 
seen, and at the Yukon mouth, on May 31, I found a pair in this plum- 
age mated. The eggs are laid on mossy knolls or uplands, in their 
haunts, about the 5th of June. The nest is merely a depression in the 
moss, containing two eggs. The young are on the wing by the end of 
July and early August. The last birds move southward or keep out to 
sea after the 20th of September. On cloudy days, or in dusky twilight, 
