212 PROCEEDINGS OF THE 



buoyant — less owl-like — than that of the Glaucous Gull. The 

 adults, when flying low or against a dark cloud, show the white 

 primaries, like a narrow strip of silver, along the wing. (The 

 wings of the Black-headed Gull (ChroicocejjJiahcs ridibunchis) have 

 this appearance also in certain eff'ects of light, but the very 

 diminutive size, and still more the tern-like flight of the latter, 

 serve at once to distinguish them). 



The Iceland Gull is by far the most wary species of gull at 

 present in the Firth. The adults are especially shy. Indeed, had 

 they proved anything like so tame as the Glaucous Gull, many 

 more specimens, I am certain, would have appeared this evening 

 on the Society's table. 



It now only remains for me to direct your attention to the 

 specimens before you. Mr Gray has described to you how the 

 birds can be distinguished in the hand, and I have endeavoured to 

 describe how they can be distinguished on the mud and in the 

 air. I need not say, that should any of the members of this 

 Society have opportunities of judging for themselves, I shall be 

 glad to hear of the results of their observations. I do not consider 

 the subject exhausted by any means ; and such an opportunity as 

 the present ofi'ers of studying the habits, postures, flight, etc., of 

 these rare Arctic strangers, should not be neglected by those who 

 have time to devote to the subject, and Avho feel sufficiently 

 interested in it. 



Mr Gray, in referring to the importance of Mr Harvie Brown's 

 observations, called attention to the specimens which had been 

 sent for illustrative purposes. These included four beautiful 

 examples of the Iceland Gull, and six Glaucous Gulls, two of 

 the latter being from, the coast of Forfarshire. 



There were also on the table some interesting skins of the 

 Herring Gull and Great Black-backed Gull, some of them being 

 in the last stage of immaturity, and others beautifully marked 

 with blue and grey on the dorsal plumage. 



