From one of the ranges I had another view of the north-west range, and we started for it, leaving the primitive country behind us.  A cold, southerly wind set in on the morning of the 18th, which made Brown and myself shiver, and I most gladly availed myself of a flannel shirt, whilst Brown covered himself with his blanket.  We rode about five hours over an undulating forest land, interrupted by one or two plains, and for the greater part exceedingly stony.  We came at last to fresh burnt grass, and observed recent marks of the stone tomahawk of the natives; and, having passed a stony slope, with irregular low stony ridges, we saw an oak-tree creek before us, on the opposite side of which rose the granitic range for which we had directed our course.  This creek also ran on the line of contact of primitive and basaltic rocks; the primitive side was cut by gullies and ravines, whilst the basalt formed a steep uninterrupted slope, though covered with boulders which had been carried down even into the sandy bed of the creek, where they were intermingled with those of granite and pegmatite.  I called this creek “Separation Creek,” in allusion to its geological relations:  at the point where we met it, it turned to the north and north-west, which made me believe that it was a westerly water; but in this I was mistaken.

We had some slight showers of drizzling rain during the afternoon.  The wind veered towards evening to the northward, and the night was clear.

We saw several kangaroos, and their tracks to the water showed that they were numerous.  One of them, which we saw in the creek, was of a light grey colour, with rich fur and a white tail.

May 19.—­We returned to the camp.  A cold easterly wind continued during the day; low rainy clouds in the morning formed into heavy cumuli during the afternoon.

My geological observations lead me to the conclusion, that an immense valley between granitic ranges has here been filled by a more modern basaltic eruption, which (supposing that Mount Lang is basaltic in the centre of elevation) rose in peaks and isolated hills, but formed in general a level table land.  The basalt has been again broken by still more recent fissures, through which streams of lava have risen and expanded over the neighbouring rock.

May 20.—­We moved our camp about eighteen miles N.N.W., to Separation Creek, the latitude of which was 18 degrees 2 minutes 22 seconds.

John Murphy found Grevillea chrysodendron in blossom, the rich orange colour of which excited general admiration.  The stringy-bark tree, and Tristania, were growing on the sandy soil, and the latter near watercourses.  Several native bustards (Otis Novae Hollandiae, Gould.) were shot, and I found their stomachs full of the seeds of Grewia, which abounded in the open patches of forest ground.  In crossing a plain we observed, under the shade of a patch of narrow-leaved tea trees, four bowers of the bowerbird, close together, as if one