We travelled in a N. 60 degrees W. direction to lat. 19 degrees 45 minutes 36 seconds.  A basaltic ridge, similar to those we had passed, extended in an almost straight line from south-east to north-west; it was covered with a scanty vegetation, with a few small narrow-leaved Ironbark trees and Erythrinas; the river now approached it, now left it in wide sweeps enclosing fine narrow-leaved Ironbark flats.  To the south-west side of this ridge or dyke, the soil is basaltic, with box-trees and open Vitex scrub.  The sharp conical hills of the white ant, constructed of red clay, were very numerous.  A very perfect bower of the bower-bird was seen in a patch of scrub trees.

In a gully, a loose violet coloured sandstone cropped out, over which the basalt had most evidently spread.  Farther on, the ridge enlarged and formed small hillocks, with bare rock cropping out at their tops;—­a form of surface peculiar to the basaltic or whinstone country of this colony.

Charley shot the sheldrake of Port Essington, (Tadorna Rajah).  The singular hissing or grinding note of the bower bird was heard all along the river; the fruit of the fig trees growing near, which seemed to supply it with its principal food during this part of the year.

April 15.—­One of our bullocks had gone back on our tracks, and thereby prevented our starting so early as usual.  We travelled in a N. 40 degrees W. direction to latitude 19 degrees 41 minutes 25 seconds.  The basaltic country continued, and apparently extended a great distance from the river.  The flats along the latter were less extensive.  Sandstone cropped out in deep gullies, and in the bed of the river; it was naturally soft and coarse, but where it rose into hillocks near basalt, it changed into a fine baked sandstone, resembling quartzite, which, when in contact with the igneous rock, looked like burnt bricks.  Near our camp, a dyke or wall of the aspect of a flinty red conglomerate, crossed the river from south-west to north-east.  I believe that this rock belongs to the porphyries of Glendon, and of the upper Gloucester.  We continued to feel the breeze, or rather a puff of wind, between 7 and 8 o’clock at night; it was often very strong and cold, and prevented the mosquitoes from molesting us.

April 16.—­We proceeded north by west to latitude 19 degrees 32 minutes, and crossed several gullies coming from the basaltic ridges:  these, however, receded far from the river, and large box and Ironbark flats took their place for about three miles, when the ridges re-appeared.  Between four and five miles from the bar of red rock above mentioned, a fine large creek joined the Burdekin from the westward.  The box and Ironbark forest was interrupted by slight rises of limestone full of corals; and by a higher hill of baked sandstone, at the foot of which a limestone hill was covered with a patch of Vitex scrub.  The strata of the limestone seemed to dip to the southward.