STEKNA FORSTERI, FOKSTER's TEEN. 679 



The history of Forster's Tern is interestiug. It is singular that so 

 couiiiion and widely-distributed a species should have remaiued unrec- 

 ognized as long as it did. Swainson and Eichardson described it as 

 the Oomiuon Tern ; Wilson did not know it at all, and Audubon only be- 

 came aware of it in the imperfect plumage which he described as " ha- 

 vein." Nuttall doubtingly gave it a name upon the strength of Eich- 

 ardson's description. Mr. Lawrence, in 1858, was the first t.o elucidate 

 its characters satisfactorily, while it was not until the appearance of my 

 paper that its changes of plumage became known. It bears, indeed, a 

 close resemblance to Wilson's Tern, yet is perfectly distinct, the curious 

 difterence in the colors of the two webs of the outer tail feathers being 

 only one of several strong characters. In (act, I learned to distinguish 

 the two species at gun-shot range, when they are in winter dress, so 

 different are they at that season. Forster's then has the crown white, 

 the occiput blackish, and a remarkably distinct black transocular fascia, 

 better marked than in any other species of ours. The bill is nearly as 

 in summer, but not so bright ; the feet are orange instead of red. This 

 plumage was finished in all of a number of old birds shot the second 

 week in September. The young-of the-year have the whole head white, 

 faintly washed with brownish, except the transocular fascia, which is 

 pure black, and very sharply defined; but nearly all the feathers of the 

 crown have dusky bases, that will increase during the fall and coming 

 winter until the condition above noticed is attained. The eye-stripe is 

 IJ inch long and about ^ an inch wide, reaching from the lores through 

 tbe eyes to and over the auriculars. The blue mantle only partly ap- 

 pears at this time, being lightly washed over with gray and clear brown ; 

 the rectrices are heavily duskj', as in hirundo at the same season, but 

 the dark color is on opposite webs in the two species. The wing-feathers 

 are new and perfect, and more hoary-silvery than those of hirnndo of 

 the same age ; but the pattern of coloration is exactly duplicated. The 

 feet are yellow, more or less obscured with dusky. 



No Tern of this country is more widely and generally distributed than 

 this one. It may be found in every part of the country, at one season 

 or another, and in the interior, especially, almost replaces hirnitdo, being 

 in fact the most characteristic of the species. Doubtless some of the 

 local quotations of ^'■Mrundo^^ from interior States really refer to this 

 species. It appears to be hardier than some of its allies, as it winters 

 on our Atlantic coast north of Long Island, while most others proceed 

 further south at this season. It is the commonest Tern, in winter and 

 during the migrations, in the harbor of Baltimore. Nevertheless, its 

 wandering's at this season are pushed to South America. On the Caro- 

 lina coast it is chiefly a migrant, but also a winter resident. Compar- 

 ing it with hirundo, it is there seen to be the more northerly species of 

 the two, migrating earlier in the spring and later in the fall, besides 

 wintering where 8. hirundo does not. A few of Forster's Terns come 

 back to the Caroliuas in August; they become abundant the following 

 mouth, and there is little or no decrease of their numbers until Decem- 

 ber, when a i»art go further south, to return the latter part of March, 

 and the rest remain. It is one of the most plentiful Terns on the harbor 

 of Beaufort in October and November, when it may be distinguished 

 at any reasonable distance with ease, Wilson's Tern being tbe only one 

 at all resembling it, and this being differently marked about tbe head at 

 this season. Quite early in the spriug it leaves for its northern breed- 

 ing-grounds, generally acquiring its complete plumage before it leaves 

 tbe United States. It breeds in the interior of British America, and 



