THE MARSH TERN. 545 



Sub-Family STERXIN^. The Terns. 



Bill rather long, usually slender, straight, sometimes with the upper mandible 

 curved at the tip, which is acutely pointed ; nostrils linear and pervious ; wings 

 elongated ; primaries long and pointed, secondaries of moderate length ; tail rather 

 long and in most species forked ; tarsi slender; anterior toes have their webs emar- 

 ginate, hind toe small ; claws moderate, curved and acute. 



These birds are mostly found on the seacoast and neighboring bays, occasionally 

 on rivers and lakes: they assemble in large numbers on the sand bars and points at 

 the mouth of inlets, are much on the wing, and are remarkable for their buoyant 

 and easy flight. Their food consists of small fishes and Crustacea, which they 

 obtain by hovering over and suddenly darting down upon : although they thus seize 

 their prey while in the water, they only occasionally swim or rest upon its surface. 



STERNA, LINN^US. 



Sterna, LINN^US, Syst. Nat. (1748). 



Bill more or less strong, about the length of the head ; the upper mandible slightly 

 curved to the tip, which is narrow and acute, the lower straight, with the junction 

 of the crura about the middle; the nostrils lateral and linear, with the frontal feath- 

 ers extending to the opening; wings long, primaries narrow and tapering, the outer 

 quill longest ; tail rather long and more or less forked ; tarsi short ; toes small and 

 slender, with the webs emarginate; hind toe short; claws slightly arched and acute. 



STERNA ARANEA. Wilson. 

 The Marsh Tern. 



Sterna aranea, Wilson. Am. Om., VIII. (1814) 143. 



Sterna Anglica, Nuttall. Man., II. (1834) 269. Aud. Orn. Biog., V. (1839) 127. 

 /$., Birds Am., VII. (1844) 81. 



DESCRIPTION. 



Adult. Upper part of the head, occiput, and sides of the head upon a line with 

 the lower eyelid, black; back and wings light bluish-gray; primaries hoary on the 

 outer webs and ashy-gray on the inner, becoming lighter towards the base ; tail 

 same color as the back, but paler, and with the outer feather nearly white ; a line at 

 the base of the upper mandible, neck in front and entire under plumage, pure-white ; 

 bill deep-black ; iris brown ; legs and feet black. 



Length, thirteen and three-quarters inches; wings in extent thirty-four, from 

 flexure ten and a half; tail, four; bill, one and three-eighths; tarsus, one inch. 



Hob. Coast of the United States as far north as Connecticut. 



I include this species in our New-England Terns on the 

 above authority. I have not met with it myself, and know 

 nothing of its habits. Wilson says, 



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