Below are insider transactions of 1,000 shares or more for publicly held companies based in Maryland or having substantial operations here. Insiders are officers, directors or owners of 10 percent or more of a corporation's stock.

Essex Corp.

Joseph R. Kurry,vice president, purchased 2,000 shares of common at 50 cents each Oct. 7 and now directly and indirectly holds 39,909 common.

Martek Biosciences

David J. Kyle,vice president, exercised an option for 4,000 shares of common at $8 each Aug. 31 and now directly holds 127,065 common.

Mid-Atlantic Real. Trust

Jack H. Pechter,director, indirectly purchased 15,100 shares of share beneficial interest at $12.25 each from Sept. 11 to Sep. 22 and now indirectly holds 15,100 shares beneficial interest.

Pub Date: 11/02/98