This afternoon Mr. Lushington and the party returned, having found the northern bank of the river to consist of low marshy ground covered with a luxuriant vegetation, and in some places with such forests of mangrove trees that it was impossible to approach the stream. They however succeeded in reaching one of the channels of the river, which was upwards of 400 yards wide; the rise and fall of tide was here about twenty feet, and the current, of course, extremely rapid. They reported the river as being, to all appearance, navigable, and that the tide only set in from the westward. THE RIVER. As the southern bank of the river was bordered by high rocky hills they saw nothing of the country in that direction. Their report was on the whole satisfactory, for it appeared that the good country still extended along the northern bank, and that we were upon the mainland. PORPOISES SEEN. A good idea may be formed of the size of the river where the party made it from the circumstance of their seeing a large shoal of porpoises. IGUANA. DENSENESS OF VEGETATION. March 7. This morning we started early in a north-easterly direction and travelled all day through a very fertile and picturesque country. On our left lay hills covered with grass, and on our right extensive plains, through which ran the Glenelg. The vegetation in these was so luxuriant that it choked the fresh water up; and whole plains were sometimes thus inundated ankle deep. The country was thinly timbered, but in general the trees were of a very great size: one particularly took my fancy, having very large leaves about the colour of those of the horse-chestnut, and which cast more shade around them than any other which I have seen in Australia. In the afternoon, as we were passing through a densely vegetated bottom, we saw a very large iguana run up a tree. This brute was of a beautiful green colour and five or six feet long; it sat on the tree, making a noise somewhat like a snake, and was the largest and ugliest of the lizard tribe which I have ever seen on land. As we could make no use of it I thought it would be wanton to kill it; so, after examining it as well as we could, we moved on, leaving it undisturbed. The black flies on this day changed their character, and became much smaller than those I had hitherto seen. March 8. We made but little progress today on account of the denseness of the vegetation, which was so luxuriant that we found great difficulty in forcing our way through it; in several instances indeed it was wholly impassable; and, after making an attempt to penetrate through a jungle, we were obliged to turn about and coast round it. The numerous streams we met with were also a serious impediment, for many of these were so muddy and deep that we had great difficulty in finding a place where we could cross. SIGNS OF NATIVES.