A careful study of the intermarriages of the sub-classes and a comparison of the inheritance of the sub-class names with that of the totem names associated with them, convinced me that each pair into which the four sub-classes fell must represent an original whole, analogous to one of the two classes of the Dieri tribe. After much and long-continued inquiry, a valued correspondent, Mr. Cyrus E. Doyle, found the complete system in a tribe of the Kamilaroi nation on the Gwydir River, in northern New South Wales. This system is given in Chapter III., and the following table gives the marriages and descents under it. The two primary classes, Kupathin and Dilbi, are omitted for shortness.

The diagram which I have used to explain the two-class system can be applied to the four sub-classes, represented by the letters a, d, c, d, and interpolated between the two classes and the totems. Diagram X. gives this arrangement. The class Kupathin is represented by A, and Dilbi by B.

Diagram X

A ${\displaystyle \scriptstyle {\left\{{\begin{matrix}\ \end{matrix}}\right.}}$	a b		B ${\displaystyle \scriptstyle {\left\{{\begin{matrix}\ \end{matrix}}\right.}}$	c d

A thus represents the class Kupathin, and a and b the pair of sub-classes Ipai and Kumbo; B represents the class Dilbi, and c and d the other pair Murri and Kubbi. The totems may be added to the sub-class by the use of numerals, as in the case of the two-class systems.

The subjoined diagram I have found useful in bringing before the mind's eye in a concise form the marriages and descents in this system, the letters being those used in the preceding diagram.