The pueblo hierarchy combines elements of ancient and colonial ritual and bureaucracy. Each gobernancia (pueblo) elects a gobernador, an assistant for a two-year term, and other officials dealing with policing. The capitán-general, appointed by the gobernadores, oversees all six regions, and along with an assistant and seven justicias, is the guardian of order and justice. Traditionally, punishment for serious offenses was public whipping in the churchyard, clearly another European custom learned from the Spanish missionaries. Meetings are held every other Sunday when the gobernador calls together the justicias to hear and resolve complaints. A lower tier of officials serves shorter terms and carries out ceremonial duties dealing with the maintenance of the church and the organizing of fiestas. The residential units, the rancherías, do not have a governing structure. The only person with quasi-authority and influence is the native curer. Some towns are divided into subsections by common references to "the people of arriba " (those who live upstream) and "the people of abajo " (those who live downstream). This division is most apparent in the loyalties and rivalries that are expressed during ceremonies, the popular foot races and ball games that take place during fiestas, and in the elaborate political hierarchy. Arriba-abajo distinctions are common throughout Latin American small towns and are not moiety divisions in the strict ethnological sense; however, they may be utilized in this manner by some indigenous groups. O'dam and Audam Sociopolitical organization is complicated by the presence of sometimes conflicting forms of land tenure and systems introduced at different times by the Spaniards and Mexicans that crosscut traditional organization. There are two forms of communal land tenure present in the region. The comunidad is an older, indigenous form, in which land is held patrilineally and inherited by sons or widows. The ejido is a form of communal land-tenure system provided for in the constitution of 1917, following the Mexican Revolution. It allocated communal lands to applicants—whether Indian, mestizo, or together—to be held as long as the land is used economically. Under the ejidal system, land is not officially or legally inheritable, but actual practice often violates this proviso. An elected body of officials governs the ejido and its economic business. Residential units found within ejidos and comunidades include towns and rancherías. Comunidades are governed by a popularly elected asamblea (assembly of voting members), who decide upon matters presented and select minor political and economic