of dead grass. It is a very bold bird at its breeding-place, and if the intruder 

 approaches too near the nest it swoops down with tremendous force at his head, 

 with outstretched legs and loud rushing of wings ; time after time it will 

 swoop, often striking the unwary naturalist with great force. On my visit to a 

 colony in Unst I was struck so often and so severely that I afterwards always 

 held a stick above my head, and found it most efficacious in warding off 

 such attacks. It is no light thing a buffet by a Great Skua, especially as he 

 usually takes one unawares from behind, knocking the hat over one's eyes, 

 and startling one rather rudely. 



About the middle of May, earlier or later according to the season, the 

 Great Skua begins to lay. Two eggs only are laid ; sometimes only one. They 

 vary in ground-colour from dark buffish brown to very pale buffish brown, 

 and are spotted and blotched with dark brown overlying markings and greyish 

 brown underlying spots. I have seen two or three specimens in which the 

 ground-colour was a very faint yellowish green, almost white, with some eight 

 or ten underlying marks of purplish grey and one or two brown surface-spots. 

 The markings are seldom very numerous or very conspicuous, as they are so 

 nearly the colour of the shell ; as a rule they are not much larger than a 

 fair-sized pea, and are usually most thickly distributed round the large end of 

 the egg. The eggs vary in length from 3^0 to 275 inches, and in breadth 

 from 2' i to i "9 inches. They somewhat resemble the brown varieties of the 

 Lesser Black-backed and Herring Gulls' eggs, but are always much rougher 

 in the texture of the shell. 



Young in down are pale chocolate-brown, slightly darker on the upper 

 parts. They leave the nest soon after being hatched, and are usually found 

 sitting surrounded by herrings of different sizes partially eaten. Round one 

 pair of young birds I saw in Unst I counted no less than eleven herrings, 

 many of them untouched. 



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