OSTRA, an ancient town of Umbria, Italy, near the modern Montenovo, S.E. of Sena Gallica (Sinigaglia). It is hardly mentioned by ancient authors, but excavations have brought to light remains of various buildings and some inscriptions exist. Pliny mentions with it another ancient town, Suasa, 5 m. W., which also did not survive the classical period.
OSTRACISM, a political device instituted, probably by Cleisthenes in 508 B.C., as a constitutional safeguard for the Athenian democracy. Its effect was to remove from Athens for a period of ten years any person who threatened the harmony and tranquillity of the body politic. A similar device existed at various times in Argos, Miletus, Syracuse and Megara, but in these cities it appears to have been introduced under Athenian influence. In Athens in the sixth prytany of each year the representatives of the Boulē asked the Ecclesia whether it was for the welfare of the state that ostracism should take place. If the answer was in the affirmative, a day was fixed for the voting in the eighth prytany. No names were mentioned, but it is clear that two or three names at the most could have been under consideration. The people met, not as usual in the Pnyx, but in the Agora, in the presence of the Archons, and recorded their votes by placing in urns small fragments of pottery (which in the ancient world served the purpose of waste-paper) (ostraca) on which they wrote the name of the person whom they wished to banish. As in the case of other privilegia, ostracism did not take effect unless six thousand votes in all were recorded. Grote and others hold that six thousand had to be given against one person before he was ostracized, but it seems unlikely that the attendance at the Ecclesia ever admitted of so large a vote against one man, and the view is contradicted by Plut. Arist. c. 7. The ostracized person was compelled to leave Athens for ten years, but he was not regarded as a traitor or criminal. When he returned, he resumed possession of his property and his civic status was unimpaired. The adverse vote simply implied that his power was so great as to be injurious to the state. Ostracism must therefore be carefully distinguished from exile in the Roman sense, which involved loss of property and status, and was for an indefinite period (i.e. generally for life). Certain writers have even spoken of the “honour” of ostracism. At the same time it was strictly unjust to the victim, and a heavy punishment to a cultured citizen for whom Athens contained all that made life worth living. Its political importance really was that it transferred the protection of the constitution from the Areopagus to the Ecclesia. Its place was afterwards taken by the Graphē Paranomōn.
There is no doubt that Cleisthenes' object was primarily to get rid of the Peisistratid faction without perpetual recourse to armed resistance (so Androtion, Ath. Pol. 22, Ephorus, Theopompus, Aristotle, Pol. iii. 13, 1284 a 17 and 36; viii. (v.), 3, 1302 b 15). Aristotle's Constitution of Athens (c. 22) gives a list of ostracized persons, the first of whom was a certain Hipparchus of the Peisistratid family (488 B.C.). It is an extraordinary fact that, if ostracism was introduced in 508 B.C. for the purpose of expelling Hipparchus it was not till twenty years later that he was condemned. This has led some critics (see Lugebil in Das Wesen . . . der Ostrakismos, who arrives at the conclusion that ostracism could not have been introduced till after 496 B.C.) to suspect the unanimous evidence of antiquity that Cleisthenes was the inventor of ostracism. The problem is difficult, and no satisfactory answer has been given. Aelian's story that Cleisthenes himself was the first to be ostracized is attractive in view of his overtures to Persia (see Cleisthenes), but it has little historical value and conflicts with the chapter in Aristotle's Constitution—which, however, may conceivably be simply the list of those recalled from ostracism at the time of Xerxes' Invasion, all of whom must have been ostracized less than ten years before 481 (i.e. since Marathon). With the end of the Persian Wars, the original object of ostracism was removed, but it continued in use for forty years and was revived in 417 B.C. It now became a mere party weapon and the farcical result of its use in 417 in the case of Hyperbolus led to its abolition either at once, or, as Lugebil seeks to prove, in the archonship of Euclides (403 B.C.). Such a device inevitably lent itself to abuse (see Aristotle, Pol. 38, 1284 b 22 στασιαστικῶς ἐχρῶντο).
Grote maintains that ostracism was a useful device, on the grounds that it removed the danger of tyranny, and was better than the perpetual civil strife of the previous century. The second reason is strictly beside the point, and the first has no force after the Persian Wars. As a factor in party politics it was both unnecessary and injurious to the state. Thus in the Persian Wars, it deprived Athens of the wisdom of Xanthippus and Aristides, while at the battle of Tanagra and perhaps at the time of the Egyptian expedition the assistance of Cimon was lacking. Further, it was a blow to the fair-play of party politics; the defeated party, having no leader, was reduced to desperate measures, such as the assassination of Ephialtes. To defend it on the ground that it created and stimulated the national consciousness is hardly reconcilable with the historic remark of the voter who voted against Aristides because he wished to hear no more of his incorruptible integrity; moreover in democratic Athens the “national consciousness” was, if anything, too frequently stimulated in the ordinary course of government. Aristotle, admitting its usefulness, rightly describes ostracism as in theory tyrannical; Montesquieu (Esprit des lois, xii. cc. 19, 29, &c.) defends it as a mild and reasonable institution. On the whole, the history of its effect in Athens, Argos, Miletus, Megara and Syracuse (where it was called Petalismus), furnishes no sufficient defence against its admitted disadvantages. The following is a list of persons who suffered ostracism:—Hipparchus (488); Megacles (487), Xanthippus (485), Aristides (483), Themistocles (471?); Cimon (461?) Thucydides, son of Melesias (444), Damon, Hyperbolus (417) and possibly Cleisthenes himself (q.v.).
Authorities.—For the procedure in O. see Appendix Photii (Porson, p. 675); see also, besides authorities quoted above, Busolt, i. 620; Müller's Handbuch, iv. i, 121; Gilbert, Gr. St. i. 446–466 and Greek Constitutional Antiquities (Eng. trans., 1895); A. H. J. Greenidge, Handbook of Greek Constitutional Antiquities (1896); histories of Greece in general. The view maintained in the text as to the number of votes necessary is supported by Duruy (H. of G. ii. 1, 36), Boeckh, Wachsmuth, &c.; opposed by Grote, Oman and (on the whole) by Evelyn Abbott. On the danger of privilegia in general see Cicero, de Legibus, iii. 4, and note that in Athens, ostracism gratuitously anticipated a crime which, if committed, would have been punishable in the popular Heliaea. Cf. also article Exile. (J. M. M.)
OSTRACODERMS or Osteacophores, the earliest and most primitive group of fish-like animals, found as fossils in Upper Silurian and Devonian formations both in Europe and in North
From the Trans. Roy. Soc. Edinburgh.
Fig. 1.—Thelodus scoticus, from the Upper Silurian of Lanarkshire, restored by Dr R. H. Traquair; about one-half nat. size.
From the Proc. Geol. Assoc.
Fig. 2.—Cephalaspis murchisoni, from the Lower Old Red Sandstone of Herefordshire, restored by Dr A. S. Woodward; about one-half nat. size.
