PRAEFECTUS CASTRŌRUM, praefect of the camp, is first mentioned in the
reign of Augustus. There was one to each legion.
PRAEFECTUS CLASSIS, the commander of a fleet. This title was
frequently given in the times of the republic to the commander of a
fleet; but Augustus appointed two permanent officers with this title,
one of whom was stationed at Ravenna on the Adriatic, and the other
at Misenum on the Tuscan sea, each having the command of a fleet.