The character of an institution can only be perfectly understood, if we examine its connection with the entire organization, and, if possible, trace its metamorphoses in the preceding stages.... The characteristic feature of the class system is that by the side of the gentile order, such as is found among the North American Indians, there is always another system of four marriage classes for the purpose of limiting sexual intercourse between certain groups of relatives. Neither the phratry nor the gens of the Kamilaroi forms a distinct territorial community. Their members are scattered among different roving hordes, and they only meet occasionally, e. g., to celebrate a feast or dance.... The origin of gentile systems out of Punaluan groups has never been proven, while we see among the Australian negroes that the classes are clearly and irrefutably in existence among the first traces of gentilism.... The class system in its original form is a conclusive proof of Morgan's theory, that the first step in the formation of systems of relationship consisted in prohibiting sexual intercourse between parents and children (in a wider sense).... It has been often disputed that the Punaluan family ever existed outside of the Sandwich Islands. But the marriage institutions of certain Australian tribes named by me prove the contrary.