Perhaps we might illustrate this peculiar relation by our system of college fraternities. Suppose that a Phi-Beta-Kappa man of Cornell meets a Phi-Beta-Kappa man of Yale. Immediately they recognize a certain brotherhood. Only the tie of clanship is vastly stronger, because it rests not on an agreement, but on a real blood relationship.
According to Indian ideas, a man and a woman of the same clan were too near kindred to marry. Therefore a man must always seek a wife in some other clan than his own; and thus each family contained members of two clans.
The clan was not confined to one neighborhood. As it grew, sections of it drifted away and took up their abode in different localities. Thus, when the original single Iroquois stock became split into five distinct tribes, each contained portions of eight clans in common. Sometimes it happened that, when a clan divided, a section chose to take a new totem. Thus arose a fresh centre of grouping. But the new clan was closely united to the old by the sense of kinship and by constant intermarriages. This process of splitting and forming new clans had gone on for a long time among the Indians—for how many hundreds of years, we have no means of knowing. In this way there had arisen groups of clans, closely united by kinship. Such a group we call a phratry.
A number of these groups living in the same region and speaking a common dialect constituted a larger union which we sometimes call a nation, more commonly a tribe.
This relation may be illustrated by the familiar device of a family-tree, thus:
Indian Family Tree.
Here we see eleven clans, all descended from a common stock and speaking a common dialect, composing the Mohegan Tribe. Some of the smaller tribes, however, had not more than three clans.