Note 129 — III. MORPHOLOGY.
Reading edition
All verbs in -ndĕre took the perfect in -sī: ascos, defes, pris, respos, etc. Lĕgĕre took ✱lĕxī ＞ leis through the analogy of the p. p. lĕctum. So fĭngĕre took ✱fĭxī ＞ feis through fĭctum; frangĕre, pĭngĕre, tangĕre did likewise (frais, peis, tais); and in Provençal cénher ＜ cĭngĕre, esténher ＜ exstĭnguĕre, plánher ＜ plangĕre followed the example of these (ceis, esteis, plais): hence all verbs in -nher have the preterit in -s.