A short treatise of five chapters on Abhidhamma topics.
It was written by Cūḷa-
The Saddhammasaṅgaha (p.64) attributes it to Dhammapāla’s teacher, Ānanda Vanaratana. Vācissara and Sumaṅgala wrote Subcommentaries (ṭīkā) on it, the first being older than the second. P.L.C.203 f.