Agnes , M. a virgin, 12 or 13 years old, beheaded at Rome under Diocletian, celebrated by Ambrose (de Offic. i. 41; de Virg. ad Marcell. i. 2), Jerome ( Ep. 97 ad demetriad. ), Augustine (Serm. 273, 286, and 354), Sulp. Sever. ( Dial. ii. 14), Prudentius ( περὶ Στεφάνων , xiv.), Venant. Fortunatus (Poem. vii. iii. 35), Aldhelm ( de Virgin. ); and by her Acta in Syriac in Assemani, Act. Mart. ii. 148 seq.; besides Acta falsely attributed to St. Ambrose, a doubtful homily of St. Maxim. Taurin., and some verses questionably assigned to pope Damasus. Her name is in the Carthag. Cal. of c. 450, Jan. 21; in Ruinart, p. 695. A church at Rome, in her honour, said to have been built under Constantine the Great, was repaired by Pope Honorius, A.D. 625–638, and another was built at Rome by Innocent X. (Assemani, Act. Mart. ii. 154, 155). See also Act. SS. Jan. 21, on which day her name stands in the black-letter calendar of our Prayer-book. Baeda and Usuard place it on Jan. 23; the Menolog. and Menaea on July 5.