the MONK, flourished A. D. 372. He was one of the Four Great Brothers (so called from their height), disciples of Pambo, the monk of Mt. Nitria (Vitae Patrum, 2.23; Pallad. Hist. Laus. 100.12, ed. Rosweyd. p. 543.) He knew the Bible by heart, and carefully studied Didymus, Origen, and the other ecclesiastical authors. In A. D. 339-341 he accompanied St. Athanasius to Rome. In A. D. 371-3, Peter II. succeeded the latter, and when he fled to Rome from his Arian persecutors, Ammonius retired from Canopus into Palestine. He witnessed the cruelties of the Saracens against the monks of Mount Sinai A. D. 377, and received intelligence of the sufferings of others near the Red Sea. On his return to Egypt, he took up his abode at Memphis, and described these distresses in a book which he wrote in Egyptian. This being found at Naucratis by a priest, named John, was by him translated into Greek, and in that form is extant, in Christi Martyrum Electi triumphi (p. 88, ed. Combefis, 8vo., Par. 1660). Ammonius is said to have cut off an ear to avoid promotion to the episcopate. (Socr. 4.23; Pallad. Hist. Laus. 100.12.)