The date of Phocas the grammarian

The generally accepted date for the Life of Virgil by Phocas, grinnmaticus urbis Romae, is in need of revision : contrary to current belief, it contains no certain indication of a date later than Donatus; it is even possible that Phocas flourished at Rome in the first half of the third century AD, and that Cassiodorus was right to place him before Censorinus, in the series of noteworthy grammarians earlier than Donatus. The year AD 238, the date of Censorinus' De die natali, may thus furnish an indication of the date of Phocas.