"p.198 except the comb and shears that lie between the ears of Twrch Trwyth son of Taredd Wledig "
Wild boar (Sus scrofa)
Creative Commons AttributionWild boar (Sus scrofa) - Credit: Brian Gratwicke

Another example of shapeshifting (see bookmark p.4), the implication being that the Twrch Trwyth (Twrch: boar; Trwyth: king/boar) is the son of a ruler who has been turned into a wild boar.