1 EXHIBIT 21 SUBSIDIARIES OF ATRION CORPORATION As of December 31, 1997 State of Subsidiary Incorporation Ownership - --------------------------------------------------------------------------------- Atrion Medical Products Alabama 100% Halkey-Roberts Corporation Florida 100% QMI Medical, Inc. Texas 100% AlaTenn Pipeline Company Alabama 100% Warrior Basin Leasing Company Alabama 100% Atrion International, Inc. U.S. V. I. 100% - -------------------------------------------------------------------------------- -62-