mined way, and certainly pecked at it, though, at the distance, this was all I could say with certainty. It is interesting if a means of defence resorted to against animals only, by some colonies of these birds, is by others employed to repel the intrusion of man also. For the habit itself, I do not remember reading of it, either in the case of terns or any other bird or animal, except one with which Swift has made us familiar—Swift, that great misanthrope, who, by the sheer force of his satire, has anticipated to some extent the reasoned truth of Darwin. As I say, I can hardly doubt that these terns acted as they did with malice prepense, yet, as their conduct is, perhaps, susceptible of another interpretation, I ought to mention that the bombardment was not continuous, but occasional only—a dropping fire, so to speak. As far as I could observe, however, the act was always in combination with the plunging sweep down, which makes me certain that, if not the mere mechanical effect of intense excitement, it was prompted by hostility—to which latter view I strongly incline.
A little way farther on I found two quite tiny terns—the other was of a fair size—lying together in the nest. There was excitement when I took up these also, but not nearly so great as just before, except, perhaps, on the part of the two parents. The first young bird had assumed almost its final appearance, though not quite able to fly. I concluded, therefore, that this had something to do with the different degree of excitement shown by the terns as a whole, but
