486 LARUS PHILADKLPHIA. 



peals of prolonged, derisive laughter. These Gulls now breed in one or two localities on 

 the southern coast of Maine, on Muskeget island, and southward, depositing the eggs early 

 in July. On Muskeget, the nests are placed in the depressions among the ivy, and the eggs 

 are often concealed by the overhanging leaves. When I first visited this islet, about fif- 

 teen years ago, there were some fifty pairs breeding there, but now, only a quarter part of 

 this number resort to the island. When the nests are aproached, the Laughing Gulls si- 

 lently leave them, and rising, circle at a great height, uttering their oddly sounding notes, 

 or will occasionally plunge downward toward the intruder. The Gulls migrate early in 

 September, with the Terns. 



LARUS PHILADELPHIA. 



Bonaparte's Gull. 

 'Sterna Philadelphia Ord. Guth., Oeog., II; 1815, 3W. 



DESCRIPTION. 



SP. Cn. Form, slender Size, small. COLOR. Adult. Back and wings, bluish-ash, with greater portion of two first, 

 and outer webs of two next, primaries, white. Outer webs of first and terminal portion of all, tipped with white. Ileiul, 

 sooty-Mack. Half ring around back of eye and remainder of plumage, white. Iris, brown, bill, black, and feet, yellow. 

 In winter, lacks the black head and there isaspot of dusky back of ear coverts. Youny. similar to winter adult, but witli 

 a line through wings, tips of secondaries, outer portion of three first primaries, and subterminal band on tail, dusky. 



OBSERVATIONS. 



Known by the small size and colors as described. Distributed in summer from the Great Lakes, northward. Win- 

 ters in Florida. 



DIMENSIONS. 



Average measurements of specimens. Length, 13'52; stretch, Sl'10; wing, 9'65; tail, 4'52; bill, 1-12; tarsus, l'38. 

 Longest specimen, M'OO; greatest extent of wing, 32'05; longest wing, 1(V25; tail, 5'05, bill, 1'25; tarsus, 1'53. Shortest 

 specimen, 12 95; smallest extent of wing, 29'S8; shortest, wing, 8'9H; tail, 4'05; bill, '98; tarsus, 1'25. 



DESCRIPTION OF NESTS AND EGGS. 



Nests, placed on the ground or rocky cliffs and composed of sea-weeds, etc. Eygs, three or four in number, oval in 

 form, varying from greenish to brown in color, spotted and blotched with brown, umber and lilac of varying shades. Di- 

 mensions from l'12x 1'38 to l'15x 1'45. 



HABITS. 



The pretty, little Bonaparte's Gulls come to us on the coast of New England, in num- 

 bers, only in autumn, usually late in August. They are fond of flying in small companies, 

 along the beaches, low down, just over the water, when they somewhat resemble Terns. I 

 found them quite common on Indian River, Florida, in winter, where they have much the 

 same habits as further, north. They breed on the Great Lakes, in Labrador, and north- 

 ward. 



LATIUS TRIDACTYLTJS. 



Kittiwake Gull. 

 Larut tridactylus LINN., Syst. Nat., I; 1766, 224. 



DESCRIPTION. 



SP. Cn. Form, robust. Size, medium. Tail, slightly forked. Hind too, very short. COLOR. Adult. Back and 

 entire wing, rather dark ashy-blue, becoming lighter toward terminal portion of primaries which have the outer webs of 

 first, tips of three outer, and subterminal band on next two, black. Remainder of plumage, white. Iris, brown, bill, yel- 

 low and feet, black. In winter, similar but with posterior portion of head and upper neck overwashed with ashy-blue. 

 Youny, similar to winter adult hut with an indistinct collar on back of neck, line through wing, outer two thirds of four 

 or five outer primaries, tip of tail, and bill, black. 



OBSERVATIONS. 



Known by the very short hind toe, slightly forked tail and yellow bill. Distributed in summer from the Gulf of St. 

 Lawrence, northward, wintering from Massachusetts, southward. 



DIMENSIONS. 



Average measurements. Length, 16-55; stretch, 36'53; wing. 12'55; tail, 5-56; bill, l'4. r >; tarsus, 1-25. Longest spec- 

 imen, 17-12: greatest extent of wing, 37-15: longest wing, 13-12: tail, 5'95:bill, 1'50: tarsus, 1'33. Shortest specimen, UVOO; 

 smallest extent of wing, 36'15; shortest wing, 12"05; tail, 4'95; bill, T40; tarsus, T25. 



