GREAT TERN. 375 



seen about all our numerous ponds, lakes, and rivers, most 

 usually near the close of the summer. 



This species inhabits Europe as high as Spitzbergen ; is 

 found on the arctic coasts of Siberia and Kamtschatka, and 

 also on our own continent as far north as Hudson's Bay. In 

 New England, it is called by some the Mackerel-gull. It 

 retires from all these places at the approach of winter to 

 more congenial seas and seasons. 



The great tern is fifteen inches long, and thirty inches in 

 extent ; bill, reddish yellow, sometimes brilliant crimson, 

 slightly angular on the lower mandible, and tipt with black ; 

 whole upper part of the head, black, extending to a point half 

 way down the neck behind, and including the eyes ; sides 

 of the neck, and whole lower parts, pure white ; wing-quills, 

 hoary, as if bleached by the weather, long and pointed ; whole 

 back, scapulars, and wing, bluish white, or very pale lead 

 colour ; rump and tail-coverts, white ; tail, long, and greatly 

 forked, the exterior feathers being three inches longer than 

 the adjoining ones, the rest shortening gradually for an inch 

 and a half to the middle ones, the whole of a pale lead colour ; 

 the outer edge of the exterior ones, black ; legs and webbed 

 feet, brilliant red lead ; membranes of the feet, deeply scal- 

 loped ; claws, large and black, middle one the largest. The 

 primary quill-feathers are generally dark on their inner edges. 

 The female differs in having the two exterior feathers of the 

 tail, considerably shorter. The voice of these birds is like the 

 harsh jarring of an opening door rusted on its hinges. The 

 bone of the skull is remarkably thick and strong, as also the 

 membrane that surrounds the brain ; in this respect resembling 

 the woodpecker's. In both, this provision is doubtless intended 

 to enable the birds to support, without injury, the violent con- 

 cussions caused by the plunging of the one and the chiselling 

 of the other. 



