a descent group is a social group whose members talk about common ancestry. a unilineal society is one in which the descent of an individual is reckoned either from the mother's or the father's line of descent. with matrilineal descent individuals belong to their mother's descent group. matrilineal descent includes the mother's brother, who in some societies may pass along inheritance to the sister's children or succession to a sister's son. with patrilineal descent, individuals belong to their father's descent group. societies with the iroquois kinship system, are typically unilineal, while the iroquois proper are specifically matrilineal.