200 BIRDS OF GUERNSEY. 



at the tip ; the eighth grey, with a broad white 

 tip. In No. 2 the fifth primary has no white tip ; 

 the sixth also has no white tip, and not so much 

 white towards the base ; the seventh is all brown, 

 slightly mottled towards the base, and only a very 

 slight indication of a white tip ; and the eighth is 

 mottled throughout. I think it worth while to 

 mention these two birds, as I have their exact 

 dates, and the difference of a year between them 

 agrees exactly with young birds which I have taken 

 in their first feathers and brought up tame. I may 

 also add, with regard to change of plumage owing 

 to age, that very old birds do not appear to get 

 their heads so much streaked with brown in the 

 winter as younger though still adult birds, as a 

 pair which I caught in Sark when only flappers, and 

 brought home in July, 1866, had few or no brown 

 streaks about their heads in the winter of 1877 8, 

 and in the winter of 1878 9 their heads are almost 

 as white as in the breeding-season. These birds 

 had their first brood in 1873, and have bred 

 regularly every year since that time, and certainly 

 have considerably more white on their primary 

 quills than when they first assumed adult plumage 

 and began to breed. Probably this increase of 

 white on the primaries as age increases, even after 

 the full-breeding-plumage is assumed, is always the 

 case in the Herring Gull, and also in both the 

 Lesser and Greater B]ack-backs, thus distinguishing 



