When in A.D. 378 Ammianus Marcellinus fails us we have for the rest of the century and, indeed, for the whole history of the Theodosian house in the East a considerable amount of varied documentation. But, lacking ‘an accurate and faithful guide’ like Ammianus, for a coherent picture of the political and military activity of the period we must have recourse to the inferior and derivative New History of Zosimus, partisan ecclesiastical histories, and late and skimpy chronicles. In these circumstances the fragments of the History of Eunapius, preserved mostly in the Excerpta of Constantine Porphyrogenitus, but also in some notices of the Suda, have considerable value. For, despite Eunapius’ clear inferiority to Ammianus as an historian, he was a contemporary of the events which he described. The fragments have been underused, which is probably due to the common, though not wholly accurate, opinion that Zosimus, being nothing more than a slavish copier of Eunapius, faithfully preserves what his source wrote. Yet (ignoring the problem of the degree of Zosimus’ dependence) he greatly condensed his source, and thus there is much in the Eunapian survivals that is not in the New History. The final fragments (80-88), to which I wish to address myself, are especially important because much of their material corresponds to a lacuna in Zosimus’ text, and the ecclesiastical historians,who make some use of Eunapius, appear to have deserted him here, probably because they found his version of events, especially those involving John Chrysostom, unpalatable.