The 5th-century Gaulish grammarian Consentius wrote an extensive treatise on errors in spoken Latin. In the Roman grammatical tradition, errors in single words are deemed to arise by means of the improper addition, removal, substitution, and misplacement of one of the constitutive elements of the word (letter, syllable, quantity, accent, and aspiration). Late grammarians assumed that the four catego- ries of change applied to accents too, but only Consentius provided an example for each of these cases. However, his discussion poses some problems. The examples of removal, substitution and misplacement of an accent all concern the word orator and present oddities such as a circumflex accent on the antepe- nultimate syllable; they were clearly made up for the sake of completeness and have no bearing on our understanding of Vulgar Latin. On the other hand, the example of addition of an accent is tríginta, with retraction of the accent on the antepenultimate syllable; this must be genuine and fits in well with current reconstructions of most Romance continuations of Latin triginta (Italian trenta, French trente, etc.) and other vigesimals (uiginti, quadraginta, etc.).