I have a 1662 version of the Aeneid, with Latin and French on facing pages, with the French having been translated by M. de Marolles, Abbé de Villeloin, [additional book info continues: À Paris, Chez Gvillavme De Lvyne, Libraire - Iuré au Palais, en la Gallerie des Morciers, à la Iustice, M. DC. LXII.]
There are four lines preceding the normal line 1 (the normal line 1 being 'Arma virumque cano...', which is line 5 in Marolles' version).
Ille ego, qui quondam gracili modulatus auena
Carmen; & egressus syluis, vicina coëgi,
Vt quamuis auido parerent arua colono;
Gratum opus agricolis: at nunc horrentia Martis
Arma virumque cano...
There is no mention of these lines having been a later insertion (including in the notes where Marolles refers to them as having been written by Vergil), but I am told by my Latin teacher that they must be an insertion, and that line 1 as written by Vergil is 'Arma virumque cano...'.
Thought I'd ask who knows anything about these lines?