(Διόγνητος).
1. Admiral of Antiochus the Great, was commissioned, in B. C. 222, to convey to Seleuceia, or the Tigris, Laodice. the intended wife of Antiochus and daughter of Mithridates IV., king of Pontus. (Plb. 5.43; comp. Clinton, F. H. iii. pp. 315, 424.) He commanded the fleet of Antiochus in his war with Ptolemy IV. (Philopator) for the possession of Coele-Syria, and did him good and effectual service. (Plb. 5.59 60, 62, 68-70.)