(Footnote.  Mr. Gould has figured an animal very like this I have described, as Petrogale lateralis, or the Stripe-Sided Rock Wallaby, from a specimen he some time afterwards got from Western Australia; but he has not noticed the beautiful kangaroo of Depuch Island.)

The specimen of the species of Helix I have above mentioned was found by Mr. Dring, one of our most successful collectors in that department.  In the Appendix are figured some of the new shells discovered during the voyage.

Leaving Depuch Island, we examined the coast to the eastward as far as the Turtle Isles, a distance of eighty-five miles, the first twenty-seven of which trended North 55 degrees East, and the remainder North 67 degrees East curving slightly inwards.  As the French had obtained a distant view of this coast, it did not possess to us the interest of being a new portion of the continent.

EFFECTS OF MIRAGE.

Still the effect of the treacherous mirage, which has often deluded the way-worn thirsty traveller with the false appearance of water, raised many parts of the interior that had not before met the eye of an European.  These presented a very level outline.  The interior was, for a great distance, a vast plain, so low that we could scarcely see it from the ship’s masthead over the sandhills, which did not exceed the height of 40 feet.  Six or seven miles from the Turtle Isles this extensive level was interrupted by the presence of a group of hills, from 200 to 300 feet in elevation, apparently of the same character as the heights behind Depuch Island.  As seen through the medium of mirage, they often had a most curious appearance:  high continuous ranges, changing again to lofty islands, danced in the tremulous air.  I should remark that when the land was subject to this distortion, it was always during the forenoon, and on those days the winds were invariably light.

APPEARANCE OF THE COAST.

The shore, for nearly fifteen miles from Depuch Island is very low, lined with mangroves, and intersected by creeks, which at high-water, when the tide rises sometimes 18 feet, are of some magnitude, and inundate much of the low land, leaving large portions of it whitened by a salt incrustation.  Beyond, as far as the Turtle Isles, the coast is fronted with a ridge of sandhills, scantily covered with vegetation (the highest, as I have already said, rarely exceeding an elevation of 40 feet) forming a barrier between the sea and the low lands behind, which, from the masthead, appeared to be thickly covered with small trees, and slightly raised from three to seven miles from the coast.  Several of the natives showed themselves at a distance, and from the numerous fires, it appeared to be a well inhabited part of the continent.  Still we saw no appearance of a stream of fresh water; and, though there were several creeks, the only opening of any consequence was forty-three miles from Depuch Island.  From its abounding with oysters we named it Oyster Inlet.  Across the mouth of it lies an islet, just within the north-eastern end of which there was a sufficient depth for the Beagle.  The formation of the island was a reddish porous sandstone.  At a native fire-place I found a piece of quartz and a large pearl oyster-shell.  The tide rose here 15 feet near full moon.