Evidently another and earlier name for the Dhammasaṅgaṇi.
The name occurs in the Sumaṅgalavilāsini (DA.i.17) in the classification of the Abhidhamma books.
Its Commentary is also referred to as the Dhammasaṅgahaṭṭhakathā. e.g., VibhA.391, 43, 105, 518; PSA.405.