Note 273 — THE AUXILIA DURING THE FIRST TWO CENTURIES A.D.
Reading edition
Praepositus is more usual, and probably the original title. Later we find the title praefectus, and the inclusion of this post at the bottom of the equestrian census, below the previous three posts, gave rise to the phrase a quattuor militiis. Cf. xiii. 6814 and von Dom. Rangordnung, p. 131.