The paper tests the hypothesis that Ireland, as peripheral zone, was a land of conservation of classical and late antique manuscript tradition and, furthermore, that from Ireland the classic cultural heritage was reimported on the continent. The philological study on the manuscript tradition and on the sources of five of the most important Irish mediaeval commentaries - the Egloga de Moralibus by Lathcen (Wendepunkte 5), the Liber de ortu et obitu patriarcharum, l'Expositio Evangelii secundum Marcum (Wendepunkte 27), the Interpretatio mystica et moralis progenitorum domini Iesu Christi (Wendepunkte 25) and the De mirabilibus sacrae Scripturae (Wendepunkte 38) - shows that these works, appear originally as schematic and the manuscript transmission has unmistakable traces of interpolation made in continental scriptoria. The identification of recensiones, progressively longiores, allows to appreciate the stages through which the Irish scriptoria knew and used the ancient Latin and Patristic literature.
