Dear Michael, Parish priests are attached to a diocese and are under the obedience of the bishop of the diocese. Other priests, including Jesuits, belong to religious orders or congregations. Often this is a worldwide jurisdiction, subject directly to the Pope.
Major monasteries are independent and are ruled by abbots.
The New Catholic Encyclopedia can give you more detailed information about various orders. Some order priests are in charge of parishes. This fact places them under the obedience of the local bishop in matters pertaining to the parish, whereas they are under their own religious order superiors in other matters. There are four seminaries in the Houston area. The diocesan seminary, St. Mary's, is at 9845 Memorial Drive, Houston 77024, tel.