322 LONG-WINGED SWIMMERS — LONGIPENNES. 



manner of Swallows. It is rarely seen on the Pacific sea-coast, and only in spring 



and fall. 



Mr. B. F. Goss found this Tern breeding in large numbers in the marshes bordering 

 small inland lakes and i)onds in Minnesota. The late Mr. R. Kennicott mentioned 

 its breeding in the Calumet marshes, on the southeastern margin of Lake Michigan ; 

 and it also breeds in large numbers in the marshes adjacent to Lake Koskonong, in 

 Southern Wisconsin, where its eggs have been taken, at different times, in consider- 

 able numbers. 



Its nest is usually placed near water — sometimes over shallows — on tufts of 

 reeds or rushes. More commonly than otherwise it builds in very wet localities, and 

 not infrequently the nest is but little raised above the level of the water. It is made 

 of coarse flags, reeds, and grasses, and lined with slender bits of the same materials. 

 The eggs — usually three — are occasionally four in number, average 1.42 inches in 

 lengtli by 1.0<> inch in breadth, and have a ground-color of a dark olive-brown, blotched 

 and spotted with bistre so deep as to have the effect of blackness. The markings are 

 in most cases quite bold, and are principally at the larger end. 



This Tern is quite celebrated for the ease and certainty with which it pursues and 

 captures, on the wing, the larger insects, such as dragon-flies and beetles. Its flight 

 is rapid, and it can stop, turn, and alter its course with all the ease of a Swallow. 



It is said to arrive in Louisiana, coming across the water from the Mexican terri- 

 tories, about the middle of April, and to continue passing through until into INIay. 

 It reappears, in the course of its southern migrations, in the months of September 

 and October. Many i)airs breed in the intermediate range between the Southern 

 States and the Great Lakes. xVudubon found it breeding on the margins of ponds near 

 the Ohio Eiver in Kentucky, and also in the neighborhood of Vincennes, Ind. 



Professor Kumlien informs me that the Black Tern is very abundant not only 

 near Lake Koskonong, but also wherever there are suitable situations, such as muddy 

 marshes, with water here and there with a depth of from a few inches to three or 

 four feet. In the large marshes, at some distance from the lake, or in a shallow bay, 

 it makes its nest of broken pieces of reeds, the nest being one large mass of reeds, 

 more or less rotten, heaped together, the whole raised from one to four inches above 

 the water. But the nests appear to vary very considerably, there being sometimes 

 hardly anything more than a simple depression, and at other times quite an elaborate 

 structure. The chick (beautifully mottled with different shades of brown) swims and 

 dives when but a few hours old. By far the greater number of the Black Terns seen 

 in the lake during the early part of summer have their nests in the adjoining marshes, 

 and only visit the lake for foraging })urposes. This bird arrives in May, and departs 

 so gradually that it is impossible to say anything more definite about the time of 

 its leaving than that by September these Terns have gone. Among the immense 

 numbers of Bhu^k Terns seen there in June comparatively few are immature birds. 



Captain Bendire found this a common summer resident in Eastern Oregon, breeding 

 in colonies in several of the sloughs in the vicinity of Silver River. He obtained a 

 large number of their eggs, nearly fresh, June 1, 187G. 



Eggs of this species in the Smithsonian Collection, from California and from 

 Pewaukee, Wis., have a ground-color varying from a deep drab, or a brownish olive, 

 to a light drab, and also to a light greenish drab. The spots are numerous, evenly 

 distributed, and are of a dull lavender-gray, brownish black, and undjer-brown, intensi- 

 fied to blackness. Specimens in my own collection, from Lake Koskonong, have the 

 following average measurements : 1.21 by .9G inches ; 1.42 by 1.00; 1.37 by 1.00; 1.36 

 by .90. 



