THE BLACK-HEADED GULL. 219 



at the recent Glasgow meeting of the British Association. I had 

 the pleasure of listening to this paper, which is printed in extenso 

 in the British Association Beport for 1901, p. 37 8. The young 

 Gulls were L. ridibundus. Prof. Thomson says : — " They [the 

 newly-hatched Gulls] pecked at the cotton-wool of their beds " 

 (loc. cit. p. 379); and further on he says again: "During the 

 first two days they got some of the cotton-wool of their beds into 

 their mouths, but this was inevitable" (p. 380). Why "inevit- 

 able " ? The Professor evidently attributes this to infantile 

 blundering, but may it not be considerably nearer the mark to 

 suggest that it was due to a longing for the dry fluffy moth-food 

 their hereditary instinct told them they should be provided with ? 

 I should have made my suggestion when it occurred to me on the 

 spot, but the formidable row of grey beards and bald heads that 

 clustered round the President of Section D was too awe-inspiring 

 to a mere listener on the back benches. 



A further but greatly less marked modification of the habits 

 of this species may also be described here. During those rather 

 infrequent bright and very still days we have in September and 

 October, when insects rise high into the air, Jackdaws and Star- 

 lings combine to hunt them, gliding backwards and forwards, 

 Swallow-like, for hours at a time. Always within my recollection 

 such gatherings have occasionally included one or two Black- 

 headed Gulls, but nowadays one never sees them without the 

 Gulls. And the latter may often preponderate in numbers. On 

 such autumn days — days which, it may be said, are invariably 

 characterized by strong migration movements — the principal in- 

 sect that is being pursued is a large black species of Chironomus. 



S2 



