SOUTH AUSTRALIA 55
subject to overflow, and no doubt can exist as to the fact of their being, at least partially, if not wholly, under water at times. A country in a state of nature is, however, so different from one in a state of cultivation, that it is hazardous to give an opinion as to its practical availableness, if I may use such a term. I should undoubtedly say the marshes of the Macquarrie were frequently covered with water, and that they were wholly unfit for any one purpose whatever. It is evident from the marks of the reeds upon the banks, that the flood covers them occasionally to the depth of three feet, and the reeds are so densely embodied, and so close to the river side, that the natives cannot walk along it. The reeds are the broad flag-reed (arundo phragenatis), and grow on a stiff earthy loam, without any accompanying vegetation; indeed they form so solid a mass that the sun cannot penetrate to the ground to nourish vegetation. On the other hand, the valley of the Murray, though covered with reeds in most places, is not so in all. There is no mark upon the reeds by which to judge of the height of inundation; neither are they of the same kind as those which cover the marshes of the Macquarrie. They are the species of round reed of which the South Sea Islanders make their arrows, and stand sufficiently open, not only to allow of a passage through, but for the abundant growth of grass among them. Still I have no doubt that parts of the valley are subject to flood; but, as I have already remarked, I do not know whether these parts are either deeply or frequently covered. Rain must fall simultaneously in the S.E. angle of the island in the intertropical regions, and at the heads of all the tributaries of the main stream, ere its effects can be felt in the lower parts of the Murray. If the valley of the Murray is not subject to flood, it has only recently gained a height above the influence of the river, and still retains all the character of flooded land. In either case, however, it contains land that is of the very richest kind
