OECADIA. 55 



large colonies — indeed, they were far more numerous than I 

 have ever observed them in the Shetlands ; but we saw no 

 other terns, though we were told, on what appeared to be 

 excellent authority, of the whereabouts of a colony of Sandwich 

 Terns. 



We were interested one day in watching the alarm of a pair 

 of Peregrines at our approach to one of the western cliffs of 

 Westray. They evidently had young. Besides the Merlin the 

 Kestrel is represented in these islands. 



We found all the British breeding species of the Laridae 

 represented : Larus marinus by a colony of half a dozen pairs 

 or so ; L. fuscus by a large and scattered colony on Hoy and a 

 smaller one on Bonsay; L. argentatus by several large colonies 

 chiefly on the cliffs; L. canus by two or three colonies and 

 numerous scattered pairs ; and L. ridibundus by two large 

 colonies. 



The fowl craig on Papa Westray affords a sight not easily 

 forgotten by the lover of bird life, being tenanted by countless 

 swarms of Kittiwakes, besides Bazorbills, Guillimots, Puffins 

 and Shags, and there are other sites perhaps as interesting. 

 The Cormorant is represented in the Orkneys, though evidently 

 not nearly so common as the Shag. 



The Oyster-catcher (Ostralegus hcematopus) is common here, 

 and no where else have I observed so many black Guillemots 

 (Uria grylle.) One spot at least affords a considerable colony 

 of this bird. 



We heard a Diver on Bonsay, and I found an egg of the Bed 

 Throated Diver (Colymbus septentrionaUs) on Hoy (19th June), 

 of course much incubated. 



A few pairs of Bichardson's Skuas inhabit Hoy, but they 

 had evidently been interfered with, as on the first day on which 

 we visited the breeding ground we found three nests with but 

 one egg in each, far advanced in incubation ; next day, how- 

 ever, I discovered a very fine pair of green grounded, boldly 

 marked eggs, belonging to a pair of light coloured birds. 



A few Bed Grouse are to be met with on the mainland and 

 on Bonsay. They appeared to be very large birds. I saw 

 four Bavens together on Westray, and the Hooded Crow is fairly 

 numerous. The Landrail nests freely in the growing crops, 



