Note 144 — Chapter I · THE EARLIEST CONSTITUTION OF ROME
Reading edition
ib. 81 “tribuni militum quod terni tribus tribubus Ramnium, Lucerum, Titium olim ad exercitum mittebantur.” On the other hand, Servius (in Aen. v. 560) says that the tribuni were so called because they presided over one-third of the whole force.