Species III. STERNA ARANEA. 



MARSH TERN. 



[Plate LXXII. Fig. 6.] 



This new species I first met with on the shores of Cape May, parti- 

 cularly over the salt marshes, and darting down after a kind of large 

 black spider, plenty in such places. This spider can travel under 

 water as well as above, and, during summer at least, seems to constitute 

 the principal food of the present Tern. In several which I opened, the 

 stomach was crammed with a mass of these spiders alone ; these they 

 frequently pick up from the pools as well as from the grass, dashing 

 down on them in the manner of their tribe. Their voice is sharper and 

 stronger than that of the Common Tern ; the bill is differently formed, 

 being shorter, more rounded above, and thicker ; the tail is also much 

 shorter, and less forked. They do not associate with the others ; but 

 keep in small parties by themselves. 



The Marsh Tern is fourteen inches in length, and thirty-four in 

 extent ; bill thick, much rounded above, and of a glossy blackness ; 

 whole upper part of the head and hind neck black ; whole upper part of 

 the body hoary white ; shafts of the quill and tail feathers pure white ; 

 line from the nostril under the eye, and whole lower parts pure white ; 

 tail forked, the outer feathers about an inch and three-quarters longer 

 than the middle ones ; the wings extend upwards of two inches beyond 

 the tail ; legs and feet black, hind toe small, straight, and pointed. 



The female, as to plumage, differs in nothing from the male. The 

 yearling birds, several of which I met with, have the plumage of the 

 crown white at the surface, but dusky below ; so that the boundaries of 

 the black, as it will be in the perfect bird, are clearly defined ; through 

 the eye a line of black passes down the neck for about an inch, reaching 

 about a quarter of an inch before it ; the bill is not so black as in the 

 others ; the legs and feet dull orange, smutted with brown or dusky ; 

 tips and edges of the primaries blackish ; shafts white. 



This species breeds in the salt marshes, the female drops her eggs, 

 generally three or four in number, on the dry drift grass, without the 

 slightest appearance of a nest ; they are of a greenish olive, spotted with 

 brown. 



A specimen of this Tern has been deposited in the museum of this 

 city. 



(41) 



