Why is Percival unable to remember his name in Chapter 12 of Lord of the Flies?

As one of the two smallest littleuns, Percival's ability to recite his name and address as he has been taught is a sign of the morals and civilized manners ingrained in him by nurturing in his former life.  In Chapter 4, his rote repetition of this information reminds him and the other youngest children of their homes and families, and they begin to wail in miserable longing for their past situations.  Percival is representative of the boys' gradual and progressive loss of all they have learned previously, the longer they run wild on the island.  When Percival is unable to remember his name in Chapter 12, it is indicative of the total loss of innocence of all the boys, and is illustrative of how far they have come from their former reality in their descent into savagery.