The rock appeared to consist in some parts of a buff calcareous sandstone, calcareous tuff; and, more abundantly, of limestone of a peculiar aspect, presenting at first sight the appearance of porphyry, but consisting of a base of compact limestone, with disseminated portions of calcareous spar, principally due to fragments of crinoidea. At a lower part in the same rock, less compact, I found a beautiful chalcedonic cast, apparently of a terebra. The calcareous sandstone consisted of grains of quartz cemented by calcareous spar, and contained fragments of shells of the littorina or turbo.* (*Footnote. Also a sriated shell (Plate 4 figure 5) near to Buccinum globulare of Phillips, Volume 2nd 16 and 15; but Mr. Sowerby thinks it is different, and more probably a Littorina, and would call it L. filosa.) Acacia pendula FIRST SEEN. On crossing another low ridge beyond this we descended to a valley in which I saw, for the first time, that beautiful shrub of the interior, the Acacia pendula. The foliage is of a light green colour and it droops like the weeping willow; the bark is rough, and the trunk seldom exceeds nine inches in diameter. The wood of this graceful tree is sweet-scented, of a rich dark-brown colour, and being very hard, it is in great request with the natives for making their boomerangs and spearheads. It appears to grow chiefly on flats which are occasionally inundated. OTHER TREES NEAR THE RIVER. During this day's journey we also met with the Callitris pyramidalis, a tree which in external appearance closely resembles some kinds of pine-tree. The wood is of a rich yellow hue, very compact, and possesses a very agreeable perfume; it grows on the drier parts of the country. We found lofty bluegum-trees (eucalyptus) growing on the flats near the Peel, whose immediate banks were overhung by the dense umbrageous foliage of the casuarina, or river-oak of the colonists. JUNCTION OF THE PEEL AND MULUERINDIE.