their movements are governed by a totally different principle, viz. that of thought transference or thought-unity—collective thinking, as I have elsewhere called it—for that is what it most suggests. If this is not the case with locusts, what, I would ask, is the alternative explanation? If great hosts of men be neither led nor of one mind where to go, they must fall into confusion, impeding one another’s movements, and this is a law which has to do with numbers merely, without respect to the species of which they are composed. It has often been noticed, however, that large crowds seem liable to be swayed suddenly by some common impulse. Locusts may fly about a district all day doing but little harm, “and at sundown,” says Dr. Munro, “the sight becomes interesting beyond description, for the whole company then appear to vie with one another in order to roost quickly.”[23] When all have found a resting-place, “every twig, branch, bush, or separate stalk of the corn or wheat or flax are completely covered, and sometimes they stick to each other”[23]—three or four deep even. “As far as the eye can see, the surface assumes a brownish-red hue. Pillars, posts, or the walls of houses are all alike to them at the time of roosting for the night.”[23] Such, then, is the Plague Locust of South Africa, which is, when at maturity, about three inches long. Some years ago, however—the exact date is not given—a larger and handsomer species made its appearance, and is thus referred to in a letter which was sent by “A Disgusted Farmer” of Grahamstown to one of the South African papers: “The new red locust, which, during the last month, has spread from the Orange River to the sea, coming apparently from the north as well as from Natal, is doing terrible damage. Everywhere fruit-trees are being destroyed—quince, apricot, fig, orange, lemon, naartje trees. Not only are the leaves eaten, but young branches are all barked, so that they are probably killed. A splendid crop of mealies, covering the whole of Peddie, Lower Albany, Alexandria, and other districts, has been entirely destroyed. Pumpkin plants are being eaten too. Vegetables of all kinds—lucerne, cattle-cabbage, and kale—are also swept away. The locusts are laying everywhere, and, no doubt, the plague will continue some years. What is the agricultural farmer to do?”[23] I do not know, but here, probably, were there locusts, he would pick out all such birds as fed on them and try to get them taken off the list of protected species, shooting them illegally all the while he was petitioning.