and the Moreton Bay ash, the latter of which seemed to be the prerogative of the Burdekin.  At its left side a basaltic ridge rose, covered with thick scrub, and at its base extended a small plain, with black soil strewed with quartz pebbles.  The river came, as well as I could judge, from the W.N.W.  Mr. Roper and Brown caught a kangaroo, but they had a dangerous ride after it, and the poor brute, when hard pressed, showed fight, and endeavoured to lay hold of Mr. Roper.

In one of the creeks I observed pegmatite; pebbles of talc-schiste and of white quartz covered the bed of the river.

May 3.—­We had to travel for a considerable distance in the bed of the river, for the hills approached close to its banks, and numerous deep gullies intercepted their slopes.  When, however, the ridges receded, we passed several fine sound flats.  The forest was open everywhere, and the grass was good, though old.  After travelling about five miles, we saw a hill to the north-east, and, when we came almost abreast of it, the river turned to the eastward, and a wild field of broken basaltic lava rendered it impossible for us to follow its banks.  The black rough masses of rock were covered with thick scrub, in which I observed numerous bottle trees with the platanus leaf.  Keeping to the westward of the scrub, I followed a creek which farther on divided in a chain of ponds, into which the waters of the field of basalt, as well as of the basaltic ridges to the westward of it, collected.  These ridges were perfectly level at their summits, and were connected with a table land which extended far to the west.  At their foot sienite, quartz rock, and leptinite, were observed.  After turning round the field of lava to the eastward, we entered into a large flat, with patches of narrow-leaved tea tree, with reedy swamps and fine flooded-gum trees, and made our camp at a strong running brook, without trees, but densely surrounded with reeds, ferns, and pothos.  This stream formed the outlet of some fine lagoons, which extended along the steep slopes of the basaltic table land.  I crossed the creek and its flat to the opposite hills.  The flat was one level sheet or floor of basalt, here and there covered with a very shallow soil, but sometimes bare, though clothed with a fair supply of grass and with scattered flooded-gum trees.  At the foot of the eastern hills, however, deep holes existed in a water-course, with black blocks of basalt heaped over each other, on which the fig tree with its dark green foliage formed a shady bower, most delightful during the heat of the day.  The hills were composed of a lamellar granite, approaching the stratified appearance of gneiss, but the leaflets of mica, instead of forming continuous layers, were scattered.  The east side of the narrow watercourse was of primitive rock, the west side basaltic.  Having passed over the hills, I made the river at their east side.  Its banks were open for access as far as the primitive rock extended, but another field of lava commenced higher up, and rendered any progress with our cattle impossible.