EXHIBIT 23.1

                    CONSENT OF INDEPENDENT PUBLIC ACCOUNTANTS

      As independent public accountants, we hereby consent to the incorporation
of our reports included in this Form 10-K, into the Company's previously filed
Registration Statements (SEC File No. 333-08249, 333-08251, 333-08257,
333-08303, 333-36785, 333-64325, 333-66903, 333-70947, and 333-70951).

                               ARTHUR ANDERSEN LLP

San Antonio, Texas
December 20, 1999