this supposed tributary, after approaching within one or two miles of the Darling where its plains were narrow, again receded from it as they widened, and finally disappeared to the left where the plains were broad, so that its junction with the Darling has not even yet been discovered. On this principle the channel of the Lachlan, as soon as it enters the plains belonging to the basin of the Murrumbidgee, may be sought for on the northern skirts of these plains, although its floods may have been found to spread in different channels more directly towards the main stream. At 12 1/4 miles we crossed a dry and shallow branch of the river, and at 14 1/2 miles we at length reached the main channel, and encamped where a considerable pond of water remained in it, surrounded by abundance of good grass. In this hole we caught some cod-perch (Gristes peelii). April 12. I sent back three men with two horses to bring on the light cart of Mr. Stapylton, intending to await its arrival (which I expected would be in five days) at the end of this day's journey. It was my object to encamp as near as possible to Regent's Lake without diverging from the route which I wished to follow with the carts, along the bank of the Lachlan. WANT OF WATER IN THE RIVER. For this purpose it was desirable to gain a bend of that river at least as far west as the most western portion of the lake, according to Mr. Oxley's survey. This distance we accomplished and more; for we were obliged to proceed several miles further than I intended, and along the bank of the river, because no water remained in its bed, until Mr. Stapylton found a good pond where we encamped after a journey of 16 1/4 miles. Notwithstanding such an alarming want of water in the river, we saw during this day's journey abundance in hollows on the surface of the plains; a circumstance clearly evincing that this river, as Mr. Oxley has truly stated, is not at all dependent for its supply on the rains falling here. The deep cracks on the plains, so abundant as to impede the traveller, seemed capable of absorbing not only the water which falls upon them, but also any which may descend from the low hills around. During our day's journey I found grey porphyry, the base consisting apparently of granular felspar with embedded crystals of common felspar and grains of hornblende. April 13. The night had been unusually warm, so much so that the thermometer stood during the whole of it at 76 degrees (the usual noonday heat) and so parching was the air that no one could sleep. A hot wind blew from the north-east in the morning, and the barometer fell 4/10 of an inch; there were also slight showers. CUDJALLAGONG OR REGENT'S LAKE. Leaving Mr. Stapylton in charge of the camp I went with a small mounted party to Cudjallagong (Regent's lake) which I found to be nine miles to the east-south-east of our tents. We passed by the place where Cudjallagong creek first leaves the river and by which this lake is supplied.