Hegesandridas, or Agesandridas (Hegesandridas, Xen.; Agesandridas, Thuc.), son of an Hegesander or Agesander, perhaps the same who is mentioned (Thuc. i. 139) as a member of the last Spartan embassy sent to Athens before the Peloponnesian war, was himself, in its twenty-first year, 411 BC, placed in command of a fleet of two and forty ships destined to further a revolt in Euboea. News of their being seen off Las of Laconia came to Athens at the time when the 400 were building their fort of Eëtionia commanding Peiraeus, and the coincidence was used by Theramenes in evidence of their treasonable intentions. Further intelligence that the same fleet had sailed over from Megara to Salamis coincided again with the riot in Peiraeus, and was held to be certain proof of the allegation of Theramenes. Thucydides thinks it possible that the movement was really made in concert with the Athenian oligarchs, but far more probable that Hegesandridas was merely prompted by an indefinite hope of profiting by the existing dissensions. His ulterior design was soon seen to be Euboea; the fleet doubled Sunium, and finally came to harbour at Oropus. The greatest alarm was excited; a fleet was hastily manned, which, with the gallies already at the port, amounted to thirty-six. But the new crews had never rowed together ; a stratagem of the Eretrians kept the soldiers at a distance, at the very moment when, in obedience to a signal from the town, the Spartan admiral moved to attack. He obtained an easy victory : the Athenians lost two and twenty ships, and all Euboea, except Oreus, revolted. Extreme consternation seized the city; greater, says the sober historian, than had been caused by the very Sicilian disaster itself. Athens, he adds, had now once again to thank their enemy's tardiness. Had the victors attacked Peiraeeus, either the city would have fallen a victim to its distractions, or by the recal of the fleet from Asia, every thing except Attica been placed in their hands. (Thuc. viii. 91, 94-96.) Hegesandridas was content with his previous success; and had soon to weaken himself to reinforce the Hellespontine fleet under Mindarus, after the defeat of Cynos-sema. Fifty ships (partly Euboean) were despatched, and were, one and all, lost in a storm off Athos. So relates Ephorus in Diodorus (xii. 41). On the news of this disaster, Hegesandridas appears to have sailed with what ships he could gather to the Hellespont. Here, at any rate, we find him at the opening of Xenophon's Hellenics; and here he defeated a small squadron recently come from Athens under Thymochares, his opponent at Eretria. (Xen. Hell. i. 1. § 1.) He is mentioned once again (lb. i. 3. § 17) as commander on the Thracian coast, B. C. 408.