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 of musical sexual selection. To quote Darwin:

"No one was able to explain the cause until Mr Meves observed that on each side of the tail the outer feathers are peculiarly formed, having a stiff sabre-shaped shaft with the oblique barbs of unusual length, the outer webs being strongly bound together. He found that by blowing on these feathers, or by fastening them to a long thin stick and waving them rapidly through the air, he could reproduce the drumming noise made by the living bird. Both sexes are furnished with these feathers, but they are generally larger in the male than in the female, and emit a deeper note."

The possibility of reproducing the sound in the manner described seems conclusive as to the cause of it. Otherwise I should have come to the conclusion, by watching the bird, that the wings and not the tail were the agency employed.

"I have just been watching for some time a snipe continually coursing through the air and making, at intervals, the well-known drumming or bleating sound,—bleating certainly seems to me the word which best expresses its quality. The wings are constantly and quickly quivered, not only when the bird rises or flies straight forward, but also during its swift oblique descents, when one might expect that they would be held rigid in the ordinary manner. From each sweep down the bird rises and beats again upwards, but when the flight has been continued long enough the wings are pressed to the sides as the plunge to earth is made, which is also one way in which the lark descends. It is during these downward flights—but not during the descent