eyes closed, and three or four of these birds singing near, so that their strains overlap and leave no silent intervals, the listener can imagine that the sound originates within himself; that the numberless fine cords of his nervous network tremble responsively to it. There are a number of natural sounds that resemble more or less closely the most unbirdlike note of this warbler--cicada, rattlesnake, and some batrachians. Some grasshoppers perhaps come nearest to it; but the most sustained current of sound emitted by the insect is short compared to the warbler's strain, also the vibrations are very much more rapid, and not heard as vibrations, and the same effect is not produced. The grasshopper warblers gave me so much pleasure that I was often at the spot where they had their little colony of about half-a-dozen pairs, and where I discovered they bred every year. At first I used to go to any bush where I had caught sight of a bird and sit down within a few yards of it and wait until the little hideling's shyness wore off, and he would come out and start reeling. Afterwards I always went straight to the same bush, because I thought the bird that used it as his singing-place appeared less shy than the others. One day I spent a long time listening to this favourite; delightedly watching him, perched on a low twig on a level with my sight, and not more than five yards from me; his body perfectly motionless, but the head and wide-open beak jerked from side to side in a measured, mechanical way. I had a side view of the bird, but every three seconds the head would be jerked towards me, showing the bright yellow colour of the open mouth. The reeling would last about three minutes, then the bird would unbend or unstiffen and take a few hops about the bush, then stiffen and begin again. While thus gazing and listening I, by chance, met with an experience of that rare kind which invariably strikes the observer of birds as strange and almost incredible--an example of the most perfect mimicry in a species which has its own distinctive song and is not a mimic except once in a while, and as it were by chance. The marsh warbler is our perfect mocking-bird, our one professional mimic; while the starling in comparison is but an amateur. We all know the starling's ever varying performance in which he attempts a hundred things and occasionally succeeds; but even the starling sometimes affects us with a mild astonishment, and I will here give one instance.