The names of these two groups, which drew in other smaller groups, became the phratry names of the newly-formed aggregate, the largest unit known to primitive society at that stage of its evolution, and corresponding roughly to what we have defined as a tribe; for it was united by bonds of friendship, and in the course of time the language, originally very different no doubt, how different we can, indeed, hardly say, must have so far coalesced, owing to the interchange of wives (in so far as a distinct woman's language, traces of which are found among some savage tribes, was not developed), as to produce a single tongue.

This theory Mr Lang has now fortified and elaborated in The Secret of the Totem, the most important new point being the demonstration of the fact that totem kins which bear names of the same significance as the phratry names are almost invariably in the eponymous phratries—a clear proof that law and not chance has determined their position.

As an explanation of the distribution of phratry names Mr Lang adopts a theory which combines the hypotheses of evolution and borrowing, and thus explains both the wide area covered by some systems, and the increasing multitude of organisations confined to small districts, which more minute research reveals. This does not, it is true, explain the geographical remoteness of different parts of the same system or of allied systems, shown to be so by the identity of phratry animal or name. Not only is Wuthera-Mallera split into two sections; but a portion of Wuthera-Yungaru seems to be in the same position; if we may take the Badieri Yungo as equivalent to Yungaru, dispersion alone suffices to explain the case; but if Yungo is derived from the Kurnandaburi, who have Mattera as the sister phratry, then we have the Badieri phratry names borrowed each from a different tribe, at any rate in appearance.

In reality this state of things affords the strongest possible support to Mr Lang's hypothesis, if only we can suppose that the formation of tribes is subsequent to the elaboration of the phratriac system. For it might well happen that an original Yungo local group divided, from economic causes, but that each half retained its original name. Under these circumstances the two portions formed connubial alliances with other groups; and in the tribes as we see the names of these split groups are found as phratry names, combined in each case with a different sister phratry name. We find for example Wuthera-Yungo, Yungo-Mattera, Matteri-Kiraru in the central area. The same theory will explain the appearance of Wuthera beside three other sister names, though here we must call in the borrowing and migration theories as well, to explain the wide area over which the names are found. We have seen that in the northern tribes one of the phratry names appears to be in each case from the same root; if this is so, we can apply to them too the split-group hypothesis.

The case of Eaglehawk-Crow is less simple. Separated from the Darling area by a considerable space lie four systems of the same name in the east of Victoria. Here it is hardly possible to assume that the latter systems have migrated; on the other hand the area covered by the Darling group suggests that it is unlikely to have been forced from its original home by pressure from outside. Perhaps it is simplest to suppose that the Wiradjeri have gradually forced their way in, wedge fashion, between the different sections, and either swallowed up the intervening members or driven them before them; this would account for the existence of the anomalous groups to the south-west.

In this area, too, we seem to have a case of the split group; but the identity of meaning of the other phratry names (Malian and Multa both mean Eaglehawk) makes it clear that it is simply a case of translation—a possibility which must be kept in mind in the other cases also. It is a common phenomenon for two tribes to have the name of one animal in common, while for that of another entirely different words are in use. The four Victorian groups appear to have borrowed the phratry names, but the centre from which they took them must remain uncertain.

It may be noted in passing that the view of Prof. Gregory, who holds that the occupation of Victoria by the blacks dates back no more than 300 years, is hardly borne out by the distribution of the phratriac systems. It is clearly improbable that they were developed in situ, for this would make the organisation of very much more recent date than we have any warrant for supposing. On the other hand it is improbable that four tribes, all with the same phratriac names, should have taken their course in the same direction, and settled in proximity to one another, at any rate, unless the natural features of the country made this course the only possible one.

To return to Mr Lang's theory, it obviously suggests, if it does not demand, that such phratries as are spread over wide areas should in the main follow the lines of linguistic or cultural areas. Our knowledge of these is hardly sufficient to enable us to say at present how far the presumption of coincidence is fulfilled; but it is certain that in more than one large area the facts are as Mr Lang's theory requires them to be.

On the other hand in New South Wales we find an area in which we fail to discern the lines on which the phratriac systems are distributed. Here, however, we are at a disadvantage in consequence of the uncertainty introduced by the unsettled question of "blood" organisations[109]. Further research may show that the supposed phratriac areas, which are apparently only portions of the Wiradjeri territory, are in reality to be assigned to the "blood" organisations, which we may probably assign to a later date than the phratries and classes.