Adjoining the Kurnū^[4] people on the southwest are the Ngunnhalgu, reaching down the Darling River from Winbar to a point a little way beyond Wilcannia. From that locality onward, down the Darling via Menindie to Cuthero, was the habitat of the Mailpurlgu tribe. From Cuthero down the Darling river to its confluence with the Murray River at Wentworth, was the country of the Maraura tribe.

The social organisation of these three great tribes—Ngunnhalgu, Mailpurlgu and Maraura—may be briefly stated as follows. The community is segregated into two phratries, whose masculine appellations are Mukkungurra and Kilpungurra. The feminine of each of these names is formed by adding ga to the masculine. Arranged in tabular form, the rules of intermarriage of the phratries and the descent of the resulting offspring will be easily understood.

In addition to the above divisions, every man, woman and child bears the name of some animal, plant or natural object, as his or her totem, which is in all cases inherited from the mother. If the mother is, for example, a magpie, the sons and daughters will be magpies also. All creation, animate and inanimate, is divided between Mukkungurra and Kilpungurra—the former possessing a certain aggregate of totems and the latter another. Members of both phratries and the various totems are scattered through all the local divisions of the tribe.

In addition to the partitions of the community into phratries and totemic groups, there is a further subdivision of the people into Muggulu and Ngipuru, meaning sluggish blood and active blood respectively, which may for convenience of reference be called ‘blood divisions’. These castes of ‘blood’ are not necessarily coincident with the other divisions. For example, a Muggulu man or woman may belong to either phratry, and the same can be said of a Ngipuru individual. Therefore the ‘blood’ castes are dispersed indiscriminately between the phratries.

There is still another repartition which can be designated ‘shade’ divisions, which are in reality an extension of the ‘blood’ castes, for the purpose of regulating where people rest under the shades of trees in the vicinity of water or elsewhere. For example, the people belonging to the Muggulu division sit down in the shadow thrown by the butt or lower partition of the tree, whilst the Ngipuru folk sit down to rest in the shade cast by the higher branches.

The castes of ‘blood’ and ‘shade’ must be considered in arranging the marriages. A man of the Muggulu blood and the butt shade marries a Ngipuruwoman of the branch shade. And in regard to the offspring, a Muggulu mother produces Muggulu children, who take their mother’s butt ‘shade’. A Ngipuru woman produces Ngipuru children, belonging to the ‘shade’ of the branches.

Some further illustrations of the intermarriages will be interesting. A Mukkungurra usually espouses a Kilpungurraga as in the table, and in that case a man’s son’s child marries a sister’s son’s child. But if a Mukkungurra takes a Mukkungurraga as his conjugal mate, that represents the marriage of a man’s son’s child to a sister’s daughter’s child. According to this law it is evident that any given man can take his wife either from his own phratry, or from the opposite phratry. Hence it becomes quite clear that there is no exogamy among the tribes we are dealing with. We have seen that the phratry and the totem are in all cases perpetuated through the woman but this does not constitute exogamy, inasmuch as a man can marry into either phratry and consequently into either aggregate of totems.

Intermarriage of individuals of the same totem is forbidden. When a Mukkungurra marries a Kilpungurraga there is no risk of a clash of the totemic prohibitions. But if a Mukkungurra marries a Mukkungurraga it would be possible for the parties to belong to the same totem. In consequence of the ‘blood divisions’ already described, a Mukkungurraga of the proper lineage could not possibly be of the same ‘blood division’ as the man. This matter is illustrated more fully in my article on the sociology of the Wongaibon tribe.^[5]

The subdivisions ‘blood’ and ‘shade’ had altogether escaped the notice of all writers on the sociology of the Australian Aborigines, and was reported for the very first time by me in 1904, as discovered by me among the Ngeumba and Kamilaroi tribes.^[6] It has also fallen on me to be the first author to report the non-existence of exogamy among the Ngeumba, Kamilaroi, Wirraidyuri, Wailwan, Wongaibon and kindred tribes in New South Wales.