PROTECTIVE COLORATION. 43 darkened, the result being a iniiforni color, with an ap- parent absence of shadow, tending to render the object invisible. Mr. Thayer clearly demonstrates his discovery by using several decoys about the size and shape of a Wood- cock's body. These he places about six inches above the ground on wire uprights, or in a row on a horizontal rod. One of these decoys he colors uniformly, above and be- low, to resemble the earth about it, or he may even give it a fine coating of the earth itself. The upper half of the other decoys is treated in exactly the same manner, but their lower half is graded to a pure white on the me- dian line below. At a distance of forty or fifty yards the uniformly colored decoy can be plainly seen, but those which are white below are entirely in^dsible until one is within twenty or thirty feet of them. After definitely locating these graded decoys the ex- periment may be repeated ; but the result will always be the same. As one slowly retreats from them they will, as by magic, seem to pass out of existence, while the one which is colored alike both above and below can be seen distinctly. One of the best arguments for the value of a protect- ive coloration is the fact that the birds themselves are such thorough believers in it. Here we have the reason why — in sportsman's parlance — game birds "lie to a dog." When there is sufficient cover, they trust to their protect- ive coloring to escape detection, and take wing only as a last resort ; but when cover is scanty, they generally rise far out of gunshot. Some Snipe and Sparrows, however, attempt to conceal themselves even on bare sand or worn grass by squatting close to the earth, with which their plumage harmonizes in color. A sitting Woodcock had such confidence in its own invisibility that it permitted itself to be stroked without leaving the nest ; but when a light snow fell, and the
