(Ἐργῖνος), a son of Clymenus and Buzyge or Budeia, was king of Orchomenos. After Clymenus was killed by Perieres at the festival of the Onchestian Poseidon, Erginus, his eldest son, who succeeded him as king, undertook to avenge the death of his father. He marched against Thebes, and surpassing the enemy in the number of his horsemen, he killed many Thebans, and compelled them to a treaty, in which they bound themselves to pay him for twenty years an annual tribute of 100 oxen. Heracles once met the heralds of Erginus, who were going to demand the usual tribute: he cut off their ears and noses, tied their hands behind their backs, and thus sent them to Erginus, saying that this was his tribute. Erginus now undertook a second expedition against Thebes, but was defeated and slain by Heracles, whom Athena had provided with arms. (Apollod. 2.4.11; Diod. 4.10; Strab. ix. p.414; Eustath. ad Hom. p. 272; Eurip. Here. fur. 220; Theocrit. 16.105.) Pausanias (9.37.2, &c.), who agrees with the other writers in the first part of the mythus, states, that Erginus made peace with Heracles, and devoted all his energy to the promotion of the prosperity of his kingdom. In this manner Erginus arrived at an advanced age without having either wife or children: but, as he did not wish any longer to live alone, he consulted the Delphic oracle, which advised him to take a youthful wife. This he did, and became by her the father of Trophonius and Agamedes, or, according to Eustathius (l.c.) of Azeus. Erginus is also mentioned among the Argonauts, and is said to have succeeded Tiphys as helmsman. (Schol. ad Apollon. Rhod. 1.185, 2.896.) When the Argonauts took part in the funeral games which Hypsipyle celebrated at Lemnos in honour of her father Thoas, Erginus also contended for a prize; but he was ridiculed by the Lemnian women, because, though still young, he had grey hair. However, he conquered the sons of Boreas in the foot-race. (Pind. O. 4.29, &c., with the Schol.) Later traditions represent our Erginus as a Milesian and a son of Poseidon. (Apollon. 1.185, &c.; Orph. Argon. 150 ; Apollod. 1.9.16; Hyg. Fab. 14; comp. Miüller, Orchom. p. 179, &c., 2nd edit.)