According to the Aṅguttaranikāya Commentary (AA.i.52), there was once a period of great disaster in Sri Lanka, known as the Caṇḍālatissa-mahābhaya. There was no food to be had, and Sakka provided the monks with a raft on which to cross the sea. Sixty monks, however, remained in Sri Lanka, guarding the scriptures. Twelve years later, when the danger was past, the monks who had left the island returned and dwelt in the Maṇḍalārāma in Kallagāma (Kālakagāma?) There the two parties of monks met and, on comparing their records of the scriptures, these were found not to differ by so much as a syllable or even a single letter.
Comparison of this story with the account given elsewhere (e.g., VibhA.445 ﬀ) of the Brāhmaṇatissa-cora-bhaya (q.v.) strongly suggests that both refer to the same account.