While the latter series of changes leads to the extinction of the class system, the process of development by the segmentation of the sub-classes seems to tend to permanence. Why this should be, it is not easy to say. It may be because the tribes along the coast, amongst whom the extinction of the class system has been most evident, are much smaller and more isolated than the tribes on the great inland stretches of country where the same conditions extend for hundreds of miles. The area occupied by a tribe like the Kurnai is small and very isolated in comparison to that occupied by the Lake Eyre tribes, but infinitely better watered and more prolific in food supplies.
The two exogamous class divisions begin the series of changes which I have described, and it may now be asked how they themselves originated. My opinion is, that it was by the same process as that by which the four arose from the two, namely by the division of an original whole, which I have referred to as the Undivided Commune.
The two classes have been intentionally divided into four and eight sub-classes, so that it does not seem to me unreasonable to conclude also that the segmentation of the hypothetical Commune was made intentionally by the ancestors of the Australian aborigines.
In his late work Mr. Andrew Lang dissents from this hypothesis,[1] and quotes a number of writers in support of his opinion to prove that the two exogamous classes had their origin in the amalgamation of two separate and independent local totem groups. Of the writers he has quoted, only one, viz. the Rev. John Mathew, has or had a personal acquaintance with the Australian blacks. He advances a similar theory to that of Mr. Lang, based on some bird myths and legends of Victorian tribes.[2] He speaks of a pristine conflict between two races of men contesting for the possession of Australia, "the taller and more powerful and more fierce Eagle-hawk race overcoming and in places exterminating the weaker, more scantily equipped sable Crows." This hypothesis, as I understand it, infers that the two class
