Caesar's revision of the senatorial list and his increase of the senate to goo was a return to the practice by which the early magistrates had chosen their own body of councillors. And though the arrangement for the automatic re plenishing of the senate was restored, yet the influence exercised by Caesar and his successors over elections secured their control over the personnel of the senate. It was regarded in the early principate as the representative of republican institutions, and Augustus took pains to divide his authority with the senate. In legislation, indeed, the senate was supreme under the principate. The legislative powers of the comitia became very gradually ex tinct ; but long before they had disappeared senatus consulta had come to take the place of leges in ordinary matters, and with this prerogative the princeps never directly interfered. The senate was left at the head of the ordinary administration of Rome and Italy, together with those provinces which, not requiring any military force nor presenting special administrative difficulties, were left to the care of the Roman people. It also retained control of the public Treasury (see AERARIUM), while the princeps administered his own treasury (fiscus). It gradually became the electing body for the annual magistracies ; and, as entrance to it was still won chiefly through the magistracy, co-optation became practically the principle of admission. On the other hand, it lost all its control of foreign administration, and though occasionally consulted by the princeps, it was entirely subordinate to him in this department.
It was to the advantage of the early Caesars to pay deference to the senate, and so give to their rule an appearance of constitution alism. Vespasian admitted Italians and provincials into the senate, with a view, no doubt, to increasing its value as a representative council of the empire, but it ceased to have any real control.
Senatorial procedure remained compar atively unchanged throughout the republic and the first three centuries of the empire. The right of summoning the senate be longed originally to the consuls, and later to the consuls, praetors, and tribunes of the plebs. In the Ciceronian period, the right belonged to them in the above order of precedence. The magis trate who summoned the senate also presided and brought business before it. He first made statements to the house on important public affairs, and might then at his discretion ask the opinion of the house or invite other senators to speak. He was expected to follow a regular order of precedence in asking for votes or speeches. When the chief senators had expressed their opinion on the motion of the president, or made proposals of their own, the house divided on the motion, or the president put to the house the various proposals made. Under the empire, all the presiding magistrate's rights were extended to the princeps, who enjoyed also the right of giving his opinion as a private senator.
The senatorial insignia were not at first distin guished from those of ex-curule magistrates. But by degrees the broad stripe (latus clavus) on the tunic and the red shoe (calceus mulleus) became distinctive of the senator (hence laticlavius, "a senator").
Certain disqualifications were attached to senators in republican times, chief of which was their exclusion from trade ; and these were increased under the principate. Failure to observe these dis qualifications, or any public disgrace or gross misconduct, was punished by removal from the senate by the censors.