38 Proceedings of the Royal Physical Society. 



disappeared from many places in the south of Scotland, and 

 I have not observed a single specimen for years, though I 

 remember it breeding in numbers in Aberlady Bay. Wild 

 ducks breed in considerable numbers on two islands m the 

 above-named loch, and I may mention that a teal succeeded 

 this season in hatcliing there no less than sixteen eggs. The 

 most remarkable influx of birds which came under my obser- 

 vation last summer occurred on the 5th of September, the 

 species being the razor-bill {Alca tor da). The island of Islay 

 is almost cut in two by an arm of the sea called Loch-in-daal, 

 which opens to the Atlantic. Its shore is almost without 

 rocks. No sea fowl breed on it, and in early summer it is 

 almost destitute of birds, though in winter it becomes a great 

 resort of migrants. On Sunday, the 4th of September, not a 

 diver of any kind was to be seen on the loch, but on the 

 following day there was a remarkable change. That morning 

 every man, and woman too, that I met told me the loch must 

 be full of herrings, because " the herring birds had come " — 

 so they expressed it. On going to the shore I saw a fair and 

 interesting sight. Loch-iu-daal is some four miles broad, 

 and about twelve miles long. On that 5th of September its 

 w^aters were as smooth and as clear as crystal, and its 

 glittering surface was literally covered with birds, whilst 

 the air was filled with plunging terns. I did not doubt 

 at first that the majority of these birds would prove to be 

 guillemots, a bird which I consider much more abundant 

 than the razor-bill. On rowing out among them, however, I 

 was surprised to find that the whole multitude was exclusively 

 composed of razor-bills. During a week that these birds 

 remained with us, I only saw half-a-dozen of their congeners, 

 the guillemots and pufiins. More than this, I was equally 

 surprised to find that a vast majority of these razor-bills w^ere 

 young birds. I could make no exact computation, but I im- 

 agine that not more than one in twenty were old birds. When 

 we remember that the razor-bill, like other auks (with one ex- 

 ception), lays but a single egg, this vast assemblage of almost 

 exclusively young birds struck me as being very singular. 



If the gmllemot is called " foolish," these young razor-biUs 

 were not very wise. They were so fearless as to allow boys 



