10/30 The place becomes in the course of a few years a sheep-farm, as these animals thrive on such herbage. As already mentioned, some plants of this family are furnished with an additional contrivance for withstanding droughts, viz., oblong tubers, which, buried deep enough beneath the soil for complete protection from the scorching sun, serve as reservoirs of sap and nutriment during those rainless periods which recur perpetually in even the most favored spots of Africa. I have adverted to this peculiarity as often seen in the vegetation of the Desert; and, though rather out of place, it may be well--while noticing a clever imitation of one process in nature by the Cape farmers--to suggest another for their consideration. |