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34 when, after some while, I found and took up another baby, almost as big as the first, there was still less demonstration than in the case of the two fluffy ones—again excepting the parents. Perhaps the boiling point of communal fury that had been aroused by my first unlawful act was not to be again reached; but birds are certainly capricious in their actions, and there is no judging from one to the next.

But, taking them at their best, why are these northern terns so much fiercer and more vengeful than those which breed in the south? Of the disposition of the latter I have had ample time to judge, and, though there was always anger when I walked over the great bank crowded with their nests, yet its manifestations were of a more ordinary kind, nor, as I say, did I notice any very acute development of it when I lifted a young one from the ground. Sometimes I think these Shetlanders look slightly smaller than the English kind, and always they seem to me to be more waspish and irritable in their disposition. Are they, therefore, of a different species—the Arctic, instead of the common tern, or vice versâ? The two, indeed, are so much alike that only an ornithologist—as ornithologists tell us—is capable of distinguishing them whilst the birds are alive and at liberty. However, as the sole mark of distinction appears to consist in a hardly appreciable difference in the length of the tarsus, it is easier to understand the difficulty than how the ornithological eye, even, unsupported by a measuring-tape, manages to surmount it. But when would any