Antiquarian writers have carefully classified the Roman tombs. We have, however, only space to remark generally, that the sepulchres were either square, circular, or pyramidal buildings, and with one entrance only, which was invariably on the side farthest from the public road. They usually consisted of a vault in which the urns and sarcophagi were deposited, and a chamber above, in which the statues or effigies of the dead were placed, and the libations and obsequies performed. These sepulchres were usually places of family interment, but sometimes they were solitary tombs. Of the latter description is the _Tomb of Caecilia Metella_, which is generally acknowledged to be the most beautiful sepulchral monument in the world. It consists of a round tower formed of immense blocks of Tiburtine stone, fixed together without cement, and adorned with a Doric marble frieze, on which are sculptured rams' heads festooned with garlands of flowers. "That they are rams' heads, must be evident to any one who will take the trouble to examine them, though they are usually denominated the heads of oxen, because the tomb itself is vulgarly called Capo di Bove. But this name is obviously derived from an ox's head, (the arms of the Gaetani family, by whom it was converted into a fortress,) which was affixed many centuries ago on the side of the tower next the Appian Way, and still remains there; and, accordingly, the vulgar name is Capo di Bove, 'the head of the ox,' in the singular--not in the plural." [Illustration: (_Tomb of Caecilia Metella_.)]