The affix aṇ comes in the sense of 'that whose purpose is this' after the words 1. viśākhā and 2. āṣāḍha when the derivative of the first is combined with manya and that of the second with daṇḍa,
As वैशाखो मन्थः, आषाढो दण्डः ॥
Vart:- So also after the words चडा &c. As चडा प्रयोजनमस्य = चौडम्, श्रद्धा प्रयोजनमस्य = श्राद्धम् ॥,