(Ἀλκίδας), was appointed, B. C. 428, commander of the Peloponnesian fleet, which was sent to Lesbos for the relief of Mytilene, then besieged by the Athenians. But Mytilene surrendered to the Athenians seven days before the Peloponnesian fleet arrived on the coast of Asia ; and Alcidas, who, like most of the Spartan commanders, had little enterprise, resolved to return home, although he was recommended either to attempt the recovery of Mytilene or to make a descent upon the Ionian coast. While sailing along the coast, he captured many vessels, and put to deaths all the Athenian allies whom he took. From Ephesus he sailed home with the utmost speed, being chased by the Athenian fleet, under Paches, as far as Patmos. (Thuc. 3.16, 26_33.) After receiving reinforcements, Alcidas sailed to Corcyra, B. C. 427; and when the Athenians and Corcyraeans sailed out to meet him, he defeated them and drove them back to the island. With his habitual caution, however, he would not follow up the advantage he had gained; and being informed that a large Athenian fleet was approaching, he sailed back to Peloponnesus. (3.69-81.) In B. C. 426, he was one of the leaders of the colony founded by the Lacedaemonians at Heracleia, near Thermopylae. (3.92.)