This chapter turns from the theory to the practice of imitating authors, which it explores in relation to Latin epic in particular. It shows how the metaphors used in the rhetorical tradition to describe the process of imitating authors also ran through the practice of imitation. The chapter begins with a discussion of the passages in Lucretius’s De Rerum Natura which consider imitatio, and shows how Lucretius’s concept of a simulacrum, or a thin film of atoms which flowed from the surface of a perceivable object, became an element within the wider language used to describe the imitation of authors. Virgil’s Aeneid played a significant part in this by associating dreams and simulacral resemblances with imitations of earlier authors, including Homer, Ennius, and Lucretius. Ghosts and dreams in the Aeneid have a particular significance: those with substantial bodily presence, such as the appearance to Aeneas of the ghost of Hector, may be associated both with ethical value and with successful imitation, while simulacral resemblances are associated with moral fallibility, and are often presented as female. The metaphors used to describe the imitation of one author by another thus also became part of the practice of imitating.