Sometimes the prize may be a very rich one, and actually within reach of the hand--challenging the hand, as it were, to grasp it, and yet presently slip away to be seen no more, although it maybe sought for day after day, with a hungry longing comparable to that of some poor tramp who finds a gold doubloon in the forest, and just when he is beginning to realize all that it means to him drops it in the grass and cannot find it again. There is not the faintest motion in the foliage, no rustle of any dry leaf, and yet we know that something has moved--something has come or has gone; and, gazing fixedly at one spot, we suddenly see that it is still there, close to us, the pointed ophidian head and long neck, not drawn back and threatening, but sloping forward, dark and polished as the green and purple weed-stems springing from marshy soil, and with an irregular chain of spots extending down the side. Motionless, too, as the stems it is; but presently the tongue, crimson and glistening, darts out and flickers, like a small jet of smoke and flame, and is withdrawn; then the smooth serpent head drops down, and the thing is gone. How I saw and lost the noble wrestling frog has been recounted in Chapter IV.: other tantalizing experiences of the same kind remain to be told in the present chapter, which is not intended for the severe naturalist, but rather for such readers as may like to hear something about the pains and pleasures of the seeker as well as the result of the seeking. One of my earliest experiences of seeing and losing relates to a humming-bird--a veritable "jewel of ornithology." I was only a boy at the time, but already pretty well acquainted with the birds of the district I lived in, near La Plata River, and among them were three species of the hummingbird. One spring day I saw a fourth--a wonderful little thing, only half as big as the smallest of the other three--the well-known Phaithornis splendens--and scarcely larger than a bumble-bee. I was within three feet of it as it sucked at the flowers, suspended motionless in the air, the wings appearing formless and mist-like from their rapid vibratory motion, but the rest of the upper plumage was seen distinctly as anything can be seen. The head and neck and upper part of the back were emerald green, with the metallic glitter usually seen in the burnished scale-like feathers of these small birds; the lower half of the back was velvet-black; the tail and tail-coverts white as snow. On two other occasions, at intervals of a few days, I saw this brilliant little stranger, always very near, and tried without success to capture it, after which, it disappeared from the plantation. Four years later I saw it once again not far from the same place. It was late in summer, and I was out walking on the level plain where the ground was carpeted with short grass, and nothing else grew there except a solitary stunted cardoou thistle-bush with one flower on its central stem above the