1. Introduction; 2. Rise of nasalized allophones of short vowels; 3. The development of *nt, *nk into PrimIr. unlenited *d, *g; 4. OIr. -icc ‘comes, reaches’; 5. Loss of a nasal before a voicless fricative; 6. OIr. téit, -tét; 7. The relation of *nt, *nk > *d, *g to the rounding of vowels by a preceding labiovelar; 8. Summary; App.: The development of PrimIr. *and, *amb, *ang.