plebeian, never attained any importance, and it was only by the adoption of a member of the noble family of Piso, that its name became enrolled in the consular Fasti. The Piso adopted by one of this gens is usually called M. Pupius Piso, and obtained the consulship in B. C. 61. We find on Greek coins the cognomen of RUFUS, which is the only surname that occurs in the gens.