on which his whole system was founded, was not only left unchallenged, but was even generally regarded as the pivotal point of the entire history of the family. It was admitted that McLennan's attempt to explain this contrast was insufficient and in contradiction with the facts enumerated by himself. But the contrast itself, the existence of two diametrically opposed forms of independent and absolute groups, one of them marrying the women of its own group, the other strictly forbidding this habit, was considered irrefutable gospel. Compare e.g. Giraud-Teulon's "Origines de la famille" (1874) and even Lubbock's "Origin of Civilization" (4th edition, 1882).
At this point Morgan's main work, "Ancient Society" (1877), inserts its lever. It is this work on which the present volume is based. Here we find clearly demonstrated what was only dimly perceived by Morgan in 1871. There is no antithesis between endogamy and exogamy; no exogamous "tribes" have been found up to the present time. But at the time when communal marriage still existed—and in all probability it once existed everywhere—a tribe was subdivided into a number of groups—"gentes"—consanguineous on the mother's side, within which intermarrying was strictly forbidden. The men of a certain "gens," therefore, could choose their wives within the tribe, and did so as a rule, but had to choose them outside of the "gens." And while thus the "gens" was strictly exogamous, the tribe comprising an aggregate of "gentes" was equally endogamous. This fact gave the final blow to McLennan's artificial structure.
But Morgan did not rest here. The "gens" of the American Indians furthermore assisted him in gaining another important step in the field under investigation. He found that this "gens," organized in conformity with maternal law, was the original form out
