of procedure, but it put into a more definite legal form a principle which the consuls had followed in a general way for many years. From this time forth the senate is a body of ex-magistrates, and very important results followed in the next century in consequence of this change in its composition. The following considerations enable us to fix approximately the date of the Ovinian law. It was a plebiscite, and since by its provisions the right to make out the list of senators was transferred from the consul to the censor, we may be sure that it was not passed until after plebeians were eligible to the censorship, that is, until after 339. The earliest lectio senatus by a censor, of which we have any record, dates from 312, so that the law must have been passed between 339 and 312. At the time of its passage plebeians were eligible to all the ordinary political offices, so that under its operation the number of plebeian senators must have increased greatly. In fact, it would be only a question of time when the majority would be plebeian.
48. The Appearance of the Nobilitas. Under the new régime the choice of senators was made indirectly by the people in their centuriate and tribal assembles. A candidate of obscure position, however, had little chance of election. Only unusual ability or a great danger enabled an ignobilis, like Marius or Cicero, to secure a political office; for, since wealth became a more and more influential factor in politics and society, and since the imagines of distinguished families appealed in a forcible, concrete way to the Roman's deeply rooted respect for the past, political office, and consequently a seat in the senate, became practically a hereditary privilege of a few rich families, and constituted the basis of a new patricio-plebeian aristocracy, the nobilitas, which from this time on took the place in the
