For some unknown reason they are totemic, one group calling itself Cockatoo, the other calling itself Crow, whilst each feels in consequence that its members are "all-one-flesh" in some mysterious and moving sense.

Again, for some unknown reason each is exogamous, so that matrimonial alliances are bound to take place across the river.

Lastly, each has mother-right of the full-blown kind.

The Cockatoo-girls and the Crow-girls abide each on their own side of the river, where they are visited by partners from across the water; who, whether they tend to stay and make themselves useful, or are merely intermittent in their attentions, remain outsiders from the totemic point of view and are treated as such.

The children, meanwhile, grow up in the Cockatoo and Crow quarters respectively as little Cockatoos or Crows.