A very conspicuous hill, bearing E.N.E. from the junction of the rivers, received the name of Mount Graham, after R. Graham, Esq., who had most liberally contributed to my expedition.

Mr. Gilbert found a large calabash attached to its dry vine, which had been carried down by the waters.  Several other very interesting cucurbitaceous fruits, and large reeds, were observed among the rubbish which had accumulated round the trees during the flood.

April 3.—­We travelled up the Burdekin, in a north-north-west direction, to latitude 20 degrees 31 minutes 20 seconds.  The country was hilly and mountainous; the soil was stony; and the banks of the river were intersected by deep gullies and creeks.  The forest vegetation was the same as that on the lower Suttor.  Among the patches of brush which are particularly found at the junction of the larger creeks with the river, we observed a large fig-tree, from fifty to sixty feet high, with a rich shady foliage; and covered with bunches of fruit.  The figs were of the size of a small apple, of an agreeable flavour when ripe, but were full of small flies and ants.  These trees were numerous, and their situation was readily detected by the paths of the natives leading to them:  a proof that the fruit forms one of their favourite articles of food.  The drooping tea trees, which had increased both in number and size, grew in company with an arborescent Calistemon, along the water’s edge; and a species of Eucalyptus, somewhat resembling Angophora intermedia, was discovered at this spot:  it occurs frequently to the northward, and is common round the gulf of Carpentaria.  The small Acacia tree of Expedition Range was frequently seen in the forest, and was covered with an amber-coloured gum, that was eatable, but tasteless:  Hakea lorea (R.  Br.), and Grevillea ceratophylla (R.  Br.); the Ebenaceous tree, and that with guava-like fruit (lareya), were all numerous.  The bed of the river was covered with the leguminous annual I noticed at the Suttor; it grew here so high and thick that my companions were unable to see me, though riding only a few yards from them.

Rock frequently crops out in the bed of the river, and in the neighbouring hills.  Several hills at the right bank were formed by a kind of thermantide of a whitish grey, or red colour, and which might be scratched easily with a penknife.  Other conical hills or short ranges, with irregular rugged crests, were composed of granite of many varieties, red and white, fine grained without hornblende, or containing the latter substance, and changing into sienite; and, at one place, it seemed as if it had broken through Psammite.  I observed quartzite in several localities, and a hard pudding-stone extending for a considerable distance.  We were, no doubt, on the transition from the depository to the primitive rocks; and a detailed examination of this interesting part of the country would be very instructive to the geologist, as to the relative age and position of the rocks.