a Roman jurist, who probably died in the lifetime of Pomponius, for Pomponius mentions him as if he were no longer living, and cites, on his authority, a constitution of the emperor Antoninus: " Pactumeius Clemens aiebat imperatorem Antoninum constituisse." (Dig. 40. tit. 7. s. 21.1.) The name Antoninus is exceedingly ambiguous, as it belongs to Pius, Marcus, L. Verus, Commodus, Caracalla, Geta, Diadumenus, and Elagabalus; but in the compilations of Justinian, the name Antoninus, without addition, refers either to Caracalla, M. Aurelius, or Pius--usually to the first; to the second, if used by a jurist who lived earlier than Caracalla, and not earlier than Marcus; to the third, if used by a jurist who was living under Pius. (Zimmern, R. R. G. i. p. 184, n. 8.) Here it probably denotes Pius, of whom Pactumeius Clemens may be supposed to have been a contemporary.