262 BIRDS OF MIDDLESEX. 



When visiting a stronghold of the Lesser Black- 

 backed Gull at the Fame Islands, in the breeding 

 season, I do not remember to have seen a single 

 individual at this time in the mottled plumage pecu- 

 liar to the immature bird. And I have remarked 

 the same thing with regard to the Blackheaded* and 

 Herring Gulls, f Independently of its smaller size, 

 the Lesser Blackbacked Gull may be distinguished 

 from its congener, the Great Blackbacked Gull, by 

 the colour of its legs, which (in adult birds) are 

 yellow; those of the larger species being flesh- 

 colour. 



HERRING GULL, Larus argentatus. An accidental 

 visitant ; no regular migration in spring and autumn 

 taking place, as in the case of the Terns. 



The few Herring Gulls which I have seen, killed 

 on the Thames and at our reservoirs (generally in 

 autumn), were all immature birds. 



In other counties I have remarked a habit of the 

 Herring Gull, when inland, of visiting newly- 

 ploughed ground, to feed on the worms and grubs 

 which are turned up ; and there can be little doubt 

 that in this respect it is a very useful bird to the 

 farmer. 



The different cry of different Gulls, although 



* See ante, p. 255. 



f See " A Visit to the Dorsetshire Coast in the Nesting 

 Season," ' Zoologist,' 1865, p. 9677. 



