1. One of the Argonauts, was a son of Neleus and Chloris, and a brother of Nestor. (Hom. Od. xi. 285 ; Apollod. i. 9. § 15; Orph. Argon. 155.) Poseidon gave him the power of changing himself into different forms, and conferred upon him great strength, but he was nevertheless slain by Heracles at the taking of Pylos. (Apollod. i. 9. § 9, ii. 7. § 3 ; Apollon. Rhod. i. 156 with the Schol.; Ov. Met. xiii. 556, &c.; Eustath. ad Hom. p. 1685.) According to Hyginus (Fab. 10) Periclymenus escaped Heracles in the shape of an eagle.
2. A son of Poseidon and Chloris, the daughter of Teiresias, of Thebes. In the war of the Seven against Thebes he was believed to have killed Parthenopaeus (Apollod. iii. 6. § 8; Paus. viii. 18, in fin.; Eurip. Phoen. 1157), and when he pursued Amphiaraus, the latter by the command of Zeus was swallowed up by the earth. (Pind. Nem. ix. 57. &c. with the Schol.)