392 LARID.E. 



yellowisli-wliite ; the iricles liazcl ; all the parts of the head 

 above the eyes black ; the feathers on the occiput elongated, 

 forming a loose plume which ends in a point ; cheeks, sides, 

 and bottom of the neck behind white ; back and wings ash- 

 grey, the ends of the tertials almost white ; the longest pri- 

 mary slate-grey, with a strong and broad white shaft, the 

 next two or three primaries each a little lighter in colour than 

 the first, and diminishing in colour in succession till they be- 

 come of the same tint as the wing-coverts ; the tail white 

 and forked ; chin, throat, neck in front, breast, and all the 

 under surface of the body pure white ; legs, toes, and their 

 membranes black, claws curved and black. The whole length 

 of the bird, from the point of the beak to the end of the 

 longest tail-feather fifteen inches. From the carpal joint to 

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

 quill-feather the longest in the wing. 



A young bird of the year killed on the 10th of August is 

 about ten inches in length ; the upper mandible dark brown, 

 the under one pale brown at the base ; forehead greyish- 

 white, top of the head and the occiput black ; back and 

 smaller wing-coverts ash-grey, varied with pale brown ; greater 

 coverts ash-grey, quill-feathers bluish-grey, the inner margins 

 white, the outside quill-feather almost black, except the shaft 

 which is white; tail-feathers varied with ash-gi-ey and brown; 

 legs, toes, and membranes dark brown. 



The young bird figured in the illustration has the head 

 mottled with black and white ; the back, wing-coverts and 

 tail-feathers varied with angular lines of black ; in this state 

 as to plumage it is the striated Tern of some authors. 



Adult birds in winter have the head white, and the old 

 bird in my own collection, killed on the lOtli of August, has 

 on the front of the head a considerable number of small 

 white feathers appearing among those which arc black. 



