Returning to the north-west coast, and tracing down the route of the third division of the parent family, from the south-east Bight of Carpentaria, towards Fort Bourke upon the Darling, we shall find, that by far the greatest and most fertile portion of New Holland appears to have been peopled by it. In its progress, offsets and ramifications would have branched off in every direction along the various ranges or watercourses contiguous to the line of route. All the rivers running towards the eastern coast, together with the Nammoy, the Gwyder, the Castlereagh, Macquarie, Bogan, Lochlan, Darling, Hume, Goulburn, etc. with their many branches and tributaries, would each afford so many routes for the different sub-divisions of the main body, to spread over the varied and fertile regions of Eastern, South-eastern, and part of Southern Australia. As tribe separated from tribe, each would retain, in a greater or less degree, some of the language, habits, or customs of the original division; but such points of resemblance would naturally again undergo many changes or modifications, in proportion to the time, distance, or isolated character of the separation. If we look at the progress of any two parties of natives, branching off upon different rivers, and trace them, either upwards or downwards, we shall find, that the further they went, the more isolated they would become, and the less likely to come again in contact with each other, or with the original division from which they separated. We may, therefore, naturally expect a much greater variety of dialects or customs in a country that is much intersected by rivers, or ranges, or by any features that tend to produce the isolating effect that I have described, than in one whose character has no such tendency; and this in reality we find to be the case. In Western and South-western Australia, as far as the commencement of the Great Bight, the features and character of the country appear to be but little diversified, and here, accordingly, we find the language of the natives radically the same, and their weapons, customs, and ceremonies very similar throughout its whole extent; but if, on the other hand, we turn to Eastern, South-eastern, and part of Southern Australia, we find the dialects, customs, and weapons of the inhabitants, almost as different as the country itself is varied by the intersection of ranges and rivers.