on some Species of British Quadrupeds, Birds, and Fishes. 287 



distinct species. So with respect to the Brown Gull, whether it is 

 or is not the Brown Tern of older authors is of no importance, as 

 at any rate it is an iminatured bird, and alike ought to be ex- 

 punged from the works on ornithology as a distinct species. 



Since the perusal of Dr. Latham's last valuable work, we scut 

 him the bird in question, bearing every mark of that described by 

 him as the Brown Cull ; and we believe the Doctor is thoroughly 

 satisfied with our observations upon it. 



It is indeed remarkable that a bird bearino- such strons marks 

 as the Black-headed Gull, in all the changes, from the nestling 

 to the adult plumage, should have ever been multiplied into so 

 many species ; as it is in its various stages readily ascertained by 

 the superior whiteness of many of the first quill feathers, espe- 

 cially on the outer webs, and the greater coverts immediately im- 

 pending them; which is very conspicuous when the wings are 

 extended, and an obvious distinguishing mark from all others, 

 even when flying. 



In order to elucidate the subject more clearly, we shall here 

 subjoin a description of the several remarkable changes incident 

 to the Black-headed Gull, which a long and intimate acquaint- 

 ance from daily observation has warranted us to assert, and from 

 which it will appear evident, that one of those mutations is the 

 identical bird in question, the Brown Gull of the Second Supple- 

 ment to the General Synopsis. In making any part of the his- 

 tory of this intricate class of birds more clear, by endeavouring 

 to bring them into the limits of truly definable distinction, we do 

 not arrogate superior knowledge on the subject, except so far 

 as favourable situations, and a strict attention to a favourite pur- 

 suit, have conspired to develop truth and undeniable facts. 



Without detailing the various synonyms of authors for this bird 

 in its several changes of plumage, we shall only have recourse to 



a few 



