BONAPARTE S GULL. 57 



round leaden-black, Avith a spot of white feathers above and 

 below the eye ; hind neck, sides of neck, and under surface of 

 body from the lower throat downwards, pure white, including 

 the under ^ving-coverts and axillaries, the lower greater coverts 

 tinged with silvery-grey like the quill-lining ; bill deep black ; 

 tarsi and toes orange-red; iris dark brown. Total length, 12-5 

 inches; culmen, .1-2; wing, 10-4; tail, 37; tarsus, 1-4. 



Adult Female,— Similar to the male. Total length_, 12-2 

 inches ; wing, io*o. 



Adult in Winter Plumaje. — Lacks the black head of the sum- 

 mer plumage, the crown being white, with some streaks of dusky- 

 grey towards the nape ; behind the eye a spot of greyish-black ; 

 tarsi and toes duller in colour. 



Young-. — Brown above, mottled with grey bases to the 

 feathers ; the crown of the head ashy-brown ; the forehead and 

 eyebrow white like the hind-neck ; sides of face white, with 

 a tinge of buff, which is found on the sides of the neck, 

 finishing on the chest ; a spot of black on the ear-coverts ; 

 wing-coverts mostly blackish, with grey bases and fulvescent or 

 whitish tips ; the secondaries with sub-terminal black markings 

 of large size ; primary-coverts white, with broad longitudinal 

 centres of black ; the primaries differing in markings from those 

 of the adults, the first one being black along both sides of the 

 shaft, the second having a little black along the- middle of the 

 inside of the shaft ; on the third the black on the inside of the 

 shaft is almost absent, but with a good deal of white on the base 

 of the outer web ; tail white, with a broad sub-terminal band 

 of black. 



Characters. — The chief characters for distinguishing Bona- 

 parte's Gull in the fully adult plumage are its black bill and 

 leaden-black hood. The differences in the young bird from 

 those of the other British species have been detailed under the 

 heading of the foregoing species. 



Range in Great Britain. — Some half-dozen examples of this 

 North American species have been obtained within our limits. 

 The first recorded was one killed near Belfast, in Ireland, in 



