In South Africa it would appear that the movements of the migratory locusts are frequently made before the Insects have acquired their wings. Mrs. Barber, in an account of "Locusts and Locust-Birds in South Africa,"[227] has illustrated many points in the {295}Natural History of these Insects. The South African species manifests the gregarious and migratory disposition when the individuals are quite young, so that they travel in flocks on foot, and are called by the Dutch "Voetgangers." After hatching, the various families of young amalgamate, so that enormous numbers come together. Having denuded the neighbourhood of all its food-supplies, they move off in search of fresh crops and pastures new. They take advantage of roads, and sometimes a good many miles will be traversed in a day; they proceed by means of short leaps, rapidly repeated. When the "Voetgangers" are thus returning northwards towards the lands in the interior from which their progenitors departed, no obstacles can stay their course. Forests or rivers may intervene, diverting them for a while from their line of march, but they succeed ultimately in continuing their journey to the interior. The manner in which these wingless locusts occasionally cross broad rivers is interesting, as it has some bearing on the difficult question of the possibility of winged locusts crossing seas of considerable width. Mrs. Barber refers to an instance that took place on the Vaal River in the spring of the year 1871, shortly after the discovery of the Diamond-fields. The country was at that time swarming with young locusts; every blade of grass was cleared off by them. One day a vast swarm of the "Voetgangers" made their appearance on the banks of the Vaal River; they appeared to be in search of a spot for crossing, which they could not find, the river being somewhat swollen. For several days the locusts travelled up the stream; in the course of doing this they paused for some time at an abrupt bend in the river where a number of rocks were cropping out, as if in doubt whether to attempt a passage at this place. They, however, passed on, as if with the hope of finding a better ford; in this apparently they were disappointed, for three days afterwards they returned to the same bend of the river, and there plunged in vast multitudes into the stream, where, assisted by a favourable current and the sedges and water-plants which grew upon the projecting rocks, they managed to effect a crossing, though great numbers were drowned and carried away by the flooded river. Mrs. Barber adds that "Voetgangers" have been known to attempt the passage of the Orange River when it was several hundred yards in breadth, pouring their vast swarms into the flooded stream regardless of the consequences, until they {296}became heaped upon each other in large bodies. As the living mass in the water accumulated, some portions of it were swept away by the strong