Sviluppi anomali e fenomeni di convergenza in alcuni dittonghi del medio-gallese

In this paper I propose an analysis of the diachronic developments of the Indo­ european diphthongs *ai and *ei in Old and Middle Welsh which, according to a general rule, yield the diphthongs oe and, respectively, wy. At the light of the somewhat phonetically puzzling (etymological) comparison between Old Irish failenn and Middle Welsh gwylan ‘seagull’ and of some analogous, unexpected oscillations in other lexical items, which apparently occur also in some placenames and in some loanwords from Latin, I advance the hypothesis that the outcomes of these two diphthongs can sometimes overlap. While the regular phonetic developments *ai > oe and *ei > wy are on the whole confirmed, anomalous outcomes can be therefore explained as the result of sporadic phenomena of merger.