A few years ago, in commenting upon certain inscriptions published by Dr. Bruce, I contended that they referred to the estates of Roman colonists called centuriæ, and not to the cohortal divisions known by the same name, as maintained by Dr. Bruce. In a later publication Dr. Bruce controverts my view and reasserts his own. Thus there is a distinct antiquarian issue between us. As such divergences of opinion will never be rare in archæology, I should have left the matter where it stood if there were not something else to import into the question, which at the time I had the honour of bringing the subject before the Society I did not think necessary to state, believing that my evidences were sufficient without it. What I now refer to, and propose to import, are two rules of the formal language of Rome, which of their own force determine the meaning of the word centuria, according as it occurs in conjunction with one quality of proper name or another.