LARID^ — THE GULLS AND TERNS — STERNA. 



291 



Sp. Char. Adult, in summer (!) : Head, axilLars, entire lining of the wing, and tail-coverts 

 (above and below) silky white ; a blacki.sh or dusky stripe on each side of the head, entirely sur- 

 rounding the eye, and extending back over the auriculars. Rest of the plumage very pale pearl- 

 gray (the lower surface uniform with the upper), the outer surface of the primaries and their 

 coverts inclining to silvery white ; inner web of outer quill chiefly white, with a stripe of plum- 

 beous-gray next the shaft ; second quill with the gray stripe paler and less sharply defined, and the 

 inner side of the web slate-gray, the edge itself narrowly white ; third quill similar, but with the 

 inner dusky stripe still more distinct, the grayish next the shaft still paler, and blended gradually 

 into the white, which is more restricted ; foiulh, fifth, and sixth quills with the dusky equally 

 distinct, and the white (except that along the edge) obsolete ; remaining quills uniform silvery 

 white. Tail uniform silvery white. Basal half of the bill brownish yellow (in the dried skin). 



the terminal half black, the tip pale yellow for about .25 of an inch ; feet pale yellowish brown 

 (in dried skin).^ Adult, in winter : Similar, but the entire lower parts and neck pure white, the 

 primaries more dusky, with the white on the inner webs more sharply defined. Bill dusky, the 

 tip yellowish. 



Wing, 9.70-10.60 inches; tail, 4.60-6.00, the depth of its fork, 1.60-2.60 ; culmen, 1.50-1.70 ; 

 depth of bill through base, .35-.46 ; tarsus, .92-. 96 ; middle toe, .75-80. 



This species in winter plumage is so similar to the same stage of S. Forsteri (== " Havelli," 

 AuD.) as to be not easily distinguished. The most obvious difference consists in the shorter and 

 less deeply forked tail, with the outer pair of rectrices broader and less elongated, their color being 

 uniform pale silvery gray or ashy white on both webs — the inner web in S. Forsteri being 

 always more or less darker than on the outer web, toward the terminal portion. The bill is also 

 stouter than in S. Forsteri, especially at the base, and the tip distinctly yellowish ; although this 

 latter feature may not prove constant. 



It is now generally believed that this species is exclusively South American, and 

 only of accidental occurrence on the southern coast of Long Island, and on that of 

 New Jersey in the neighborhood of Absecom Beach. I am not aware that any 

 specimens have been observed within the United States since it was first described by 

 Audubon. It was first noticed within our limits by Dr. Trudeau, who is said to have 

 obtained several examples at the above-named beach, in the southern part of New 

 Jersey. It is stated by Giraud as having been observed on Long Island in the adult 

 form, but never in the immature. The bird obtained by Dr. Trudeau in the vicinity 

 of Great Egg Harbor was in the company of a few others of the same kind. 



We have no information in regard to its specific peculiarities of habits. 



1 " Bill black, with part of the base of the lower mandible, the edges of both mandibles, and their tips 

 to the length of about five-twelfths of an inch, yellow ; iris brown ; feet orange-yellow, claws dusky 

 yellow" (Audubon). 



