CLĬPĔUS (ἀσπίς), the large shield worn by the Greeks and Romans, which was originally of a circular form, and is said to have been first used by Proetus and Acrisius of Argos, and therefore is called _clipeus Argolicus_, and likened to the sun. But the clipeus is often represented in Roman sculpture of an oblong oval, which makes the distinction between the common buckler and that of Argos. The outer rim was termed ἄντυξ by the Greeks; and in the centre was a projection called ὀμφάλος or _umbo_, which served as a sort of weapon by itself, or caused the missiles of the enemy to glance off from the shield. In the Homeric times, the Greeks merely used a leather strap (τελαμών) to support the shield, but subsequently a handle (ὄχανον or ὀχάνη). The usual form of the clipeus is exhibited in the figure of the Greek warrior on p. 41. When the census was instituted by Servius Tullius at Rome, the first class only used the _clipeus_, and the second were armed with the _scutum_ [SCUTUM]; but after the Roman soldiery received pay, the _clipeus_ was discontinued altogether for the _scutum_. CLĪTELLAE, a pair of panniers, and therefore only used in the plural number. CLŎĀCA, a sewer, a drain. Rome was intersected by numerous sewers, some of which were of an immense size: the most celebrated of them was the _cloaca maxima_, the construction of which is ascribed to Tarquinius Priscus. It was formed by three tiers of arches, one within the other, the innermost of which is a semicircular vault of 14 feet in diameter. The manner of its construction is shown in the preceding cut. Under the republic, the administration of the sewers was entrusted to the censors: but under the empire, particular officers were appointed for that purpose, called _cloacarum curatores_, who employed condemned criminals in cleansing and repairing them. [Illustration: Cloaca Maxima at Rome.] CŌA VESTIS, the Coan robe, was a transparent dress, chiefly worn by women of loose reputation. It has been supposed to have been made of silk, because in Cos silk was spun and woven at a very early period. [Illustration: Coa Vestis. (From a Painting at Herculaneum.)] CŎACTOR, the name of collectors of various sorts, _e.g._ the servants of the publicani, or farmers of the public taxes, who collected the revenues for them, and those who collected the money from the purchasers of things sold at a public auction. Horace informs us that his father was a coactor of this kind. Moreover, the servants of the money-changers were so called, from collecting their debts for them. The “coactores agminis” were the soldiers who brought up the rear of a line of march.