Sandstone, Old Red.—Found on various parts of Yass Plains, in contact with
Limestone, Transition.—Colour dark grey; composes the bed of the Yass River, and apparently traverses the sandstone formation. Yass Plains lie 170 miles to the S.W. of Sydney.
Sandstone, Old Red.—Again succeeds the limestone, and continues to the N.W. to a considerable distance over a poor and scrubby country, covered for the most part with a dwarf species of Eucalyptus.
Granite.—Colour grey; feldspar, black mica, and quartz: succeeds the sandstone, and continues to the S.W. as far as the Morumbidgee River, over an open forest country broken into hill and dale. It is generally on these granite rocks that the best grazing is found.
Greywacke.—Colour grey, of light hue, or dark, with black specks. Soft.—Composition of a part of the ranges that form the valley of the Morumbidgee.
Serpentine.—Colour green of different shades, striped sulphur yellow; slaty fracture, soft and greasy to the touch. Forms hills of moderate elevation, of peculiarly sharp spine, resting on quartz. Composition of most of the ranges opposite the Doomot River on the Morumbidgee, in lat. 35 degrees 4 minutes and long. 147 degrees 40 minutes.
Quartz.—Colour snow-white; formation of the higher ranges on the left bank of the Morumbidgee, in the same latitude and longitude as above; showing in large blocks on the sides of the hills.
Slaty Quartz, with varieties.—Found with the quartz rock, in a state of decomposition.
Granite.—Succeeds the serpentine, of light colour; feldspar decomposed; mica, glittering and silvery white.
Sandstone, Old Red.—Composition of the more distant ranges on the Morumbidgee. Forms abrupt precipices over the river flats; of sterile appearance, and covered with Banksias and scrub.