The old Commentary on the Tipitaka which contained the Mahávihára tradition.
It was supposed to have been compiled by, or at least under, Mahinda.
Buddhaghosa learnt it under Sanghapála and retranslated it into the Magadha (Páli) tongue, while living in the Ganthákara-parivena (Cv.xxxvii.228-234).
It evidently contained a great deal of historical material as well.
For its nature and contents see MT. Introd. lvii ff.