“However, all I saw was a charred stump of a tree and a few blackened logs or stones lying at its feet. The hunter declared that neither the tree nor the stones were there the last time we passed, and that they were simply naked Barea, who had placed themselves in that position to observe us, having no doubt seen us for some time, and prepared themselves.
“I could scarcely believe it possible they could be so motionless, and determined to explore a little. The rest of the party advised me to continue quietly in the road, as it was possible that, from our presenting a rather formidable appearance, we should pass unmolested; but so confident was I of his mistake, that, telling the rest to go on slowly, as if nothing had been observed, I dropped into the long grass and stalked up towards them.”
“A shot from my rifle at a long distance (I did not venture too close) acted on the trees and stones as powerfully as the fiddle of Orpheus, but with the contrary effect; for the tree disappeared, and the stones and logs, instead of running after me, ran in the opposite direction.”
“I never was more astonished in my life, for so complete was the deception that even up to the time I fired I could have declared the objects before me were vegetable or mineral—anything, indeed, but animal. The fact was that the cunning rascals who represented stones were lying flat, with their little round shields placed before them as screens.”
This stratagem is shown on the right hand of the illustration.
On the left are a few of the innumerable instances in Nature where Concealment is obtained by imitation.
The three examples which are here given are familiar to all entomologists.
The upper figure represents two of the Geometra or Looper Caterpillars, as they appear when at rest, and affixed to a twig. This appears to be a singular attitude of rest, but it is one in which they delight, and in which they remain for hours together, the claspers at the end of the body tightly grasping the branch, and the whole body held out so straight and motionless that it is hardly possible to believe that a veritable twig is not before the eye. The colour is that of the twig, and the different segments of the body look exactly like the little irregularities and projections of a young twig.
I have more than once seen a novice in entomology unable to distinguish these larvæ, even when the branch was pointed out, and there were several upon it.
Just below the Loopers, and on the left hand of the illustration, is shown the well-known Leaf-insect (Phyllium). These strange beings have the elytra and the flattened appendages of the legs so exactly like leaves that the most experienced eye can scarcely distinguish them from the leaves among which they are placed. Even when they have been on a small plant, such as a myrtle in a flower-pot, I have had the greatest difficulty in finding them, and have seen people examine the plant, and then go away declaring that no insects were on it.