DENTIL, in architecture, a small, rectangular block, used in a row as a decoration for the bed-moulding of a cornice. It is undoubtedly a decorative interpretation in stone of projecting beam ends in earlier wooden construction, and many of the famous rock cut tombs of Lycia, in Asia Minor, which represent wooden structures, show similar forms. Moreover, the tomb of Darius at Nakshi Rustan (c. 485 B.c.), which represents the entire front of a Persian palace, plainly shows the beam ends appearing as a dentil band. In ordinary classic usage the dentil decorates the cornices of the Ionic and Corinthian orders (see ORDER). The Attic custom, followed generally by the Romans and the Renais sance architects, kept the dentil relatively small, and spaced the dentils with an inter-space of about half the width of the block itself. Occasionally, as in the Pantheon at Rome (c. 12o), an unbroken band, known as a dentil band, replaces the separate dentils. In the Hellenistic temples of Asia Minor, such as the great temple of Athena Polias at Priene (c. 35o B.c.), a special type of heavy Ionic entablature is used, in which the dentils are much enlarged, more widely spaced, and resemble brackets. The Byzantine dentil was a specific type of band ornament, pos sibly with little relation to the classic dentil, and was used espe cially as a border for panels. It consists of an alternation of projecting blocks with splayed faces between, usually arranged in a double band, with the blocks on one side of the centre, in every case opposite the splays on the other. It is so found border ing the marble panels of S. Sophia at Constantinople (6th cen tury), and became a favourite ornament in Venice, where it was used not only as a panel mould but also as a horizontal band and even around arches.