298 LONG-WINGED SWIMMERS — LONGIPENNES. 



of the Elizabeth Ishxnds, I had an excellent opportunity of observing its habits. 

 Inclusive of the young birds, it was estimated that there were about one thousand of 

 these birds on the southern portions of that island. They nested on the uplands, 

 from a few yards to a hundred rods or more from the water, and their nests varied 

 from a mere depression in the ground, with scanty and loose linings, to quite an 

 elaborate interweaving of flags. The usual number of eggs was two ; but frequently 

 there was only one, and more rarely three. This ma_) have been owing to the 

 lateness of the season. In one or two instances there were five eggs in the same 

 depression ; but these I presume to have been laid by at least two females, and they 

 Avere watched over by several birds, which vied with each other in resenting any 

 intrusion near their common treasures. There were many young birds of various 

 ages about the breeding-grounds, and these were abundantly supplied with young 

 fry of the mackerel. I had no doubt that other birds than their parents aided in 

 this supply. The number of old birds was at least ten times that of the young ; and 

 nearly all seemed to join in the task of fishing and feeding the young birds, who 

 were kept perfectly stuffed, and grew in size surprisingly fast. 



This appears to be a very restless and a very noisy bird. It passes most of its 

 time, from early morning until late in the evening, in the air, flying about over the 

 beach, or marsh, as if in pursuit of insects, or skimming swiftly over the surface of 

 the water in pursuit of small fish, which it seizes without pausing in its flight. At 

 other times it may be seen hovering over a shoal of fish ; and the instant these come 

 to the surface it dashes headlong upon its prey, partially submerging itself in its 

 effort. It is very buoyant on the water, and swims lightly, but never dives, other 

 than by a partial plunge in fishing, and is seldom seen on the surface of the water. 

 It may often be seen, at low water, resorting to sandbars and shoals, in company 

 with smaller Gulls, picking up marine insects, small shell-fish, and other forms that 

 abound in such places. Like several other species, it is eminently social in its dis- 

 position, moving about in large companies, and keeping up a continuous interchange 

 of cries. It is often found associating with, and breeding in the same locality with, 

 the Larus atr'willa, with which it is always on good terms. Like its associate, even 

 when not pursued by the hunter, it is timid and watchful. When one of its kind is 

 wounded and falls into the water, those within hearing of its shrill outcries collect 

 around the spot, where, as they hover over their stricken companion, they afford an 

 easy mark to any disposed to continue the work of destruction. 



In some localities — as on the south side of Long Island, and where their breeding- 

 places are mere collections of sand — their eggs are laid on the bare ground, without 

 any preparation of a nest other than a slight excavation made loosely in it, and are 

 hatched chiefly by the heat of the sun's rays and by that of the sand itself, Avhich 

 retains its elevated temperature until late in the evening. The females usually sit 

 upon their eggs only at night and during unpleasant weather. They are not, how- 

 ever, neglectful of their charge, but remain near at hand, and make their presence 

 manifest if their nest is approached. If the eggs are incubated, both parents hover 

 directly above their nest, so that where there are several species breeding together, 

 each can easily be referred to its proper nest. If the young are hatched out, the 

 parent bird is all the more clamorous, and plunges in the direction of the head of 

 the intruder, occasionally striking at him with its wing, or letting fall foecal matter 

 upon the object of its displeasure. 



A few birds of this species breed every summer in the marshes bordering Lake 

 Koskonong, in Southern Wisconsin, from which locality I have received both nests 

 and eggs. The former, made of coarse water-plants, are remarkably elaborate 



