Kin Groups and Descent. The politically dominant kin groups are village-based, patrilineal descent groups that can loosely be called patricians, internally differentiated into Lineages. These groups are concerned primarily with land and sea tenure, but they also participate in exchange. People inherit group membership from their fathers; in some areas women adopt their husband's on marriage. There are also provincewide matriclans that do not have complex internal differentiation, though their importance varies around Manus. These matriclans are concerned mainly with health: treating pollution caused by contact with forbidden items, purification at stages of the life cycle. In addition there are local cognatic stocks (with patrilateral biases), one descending from each married couple in the past and present. These relationships are activated primarily during ceremonial exchanges, and as exchanges are frequent and important economically, these stocks are important. Villagers inherit all the stock Memberships of both parents.
Kinship Terminology. Terminology varies, but it Commonly stresses the relationship between the descendants of brothers and of sisters. Generational skewing of the Crow type occurs.