152 STERNA ARANEA. 



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, mor<> 

 rounded above, and thicker j 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 si lightest 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 [Philadelphia.] 



