ARCTIC TERN. 403 



breeds in great numbers on Coquet Island, a few miles south 

 of the Farn Islands. The eggs, two or three in number, are 

 very much like those of the Common Tern in shape, colour, 

 and markings, but always smaller in size, measuring one inch 

 seven lines in length, by one inch and one line in breadth. 



The adult bird in summer has the bill coral-red, the ex- 

 treme point sometimes black ; forehead, crown, and nape 

 black ; back, wings, and wing-coverts pearl-grey ; outer web 

 of the first primary lead-grey : tail-coverts and tail-feathers 

 almost white, the two longest tail-feathers on each side grey 

 on the outer webs ; cheeks white ; chin and upper part of 

 neck in front, and on the sides ash-grey ; breast and all the 

 under surface of the body as dark a grey colour as that of 

 the back ; legs, toes, and their membranes orange-red. The 

 whole length of the bird from the point of the bill to the end 

 of the middle, or short, tail-feather twelve inches and a half, 

 to the end of the longest tail-feather two inches and a half 

 more, or fifteen inches whole length ; from the wrist to the 

 end of the longest quill-feather eleven inches ; length of the 

 tarsus only half an inch. 



A young bird of the year, nearly full grown, and measur- 

 ing thirteen inches, has the bill dull brown at the point, the 

 remainder red ; forehead dull white ; crown of the head 

 mottled black and white ; back of the head and nape uniform 

 dusky black ; back and wings pearl-grey ; outer web of the 

 first primary lead-grey, inner webs of all the primaries light 

 grey, almost white ; secondaries, tertials, scapulars, and small 

 wing-coverts tipped with white ; upper tail-coverts and tail- 

 feathers white, the three long tail-feathers on each side with 

 outer webs of slate-grey ; throat, breast, and all the under 

 surface of the body and wings at this age nearly pure white ; 

 legs, toes, and membranes orange. 



The winter-plumage of the adult bird has not been ob- 

 served. 



2 D 2 



