There is the substitution of n for the initial ṇ of the root in the dhātupāṭha,
The phrase धात्वादेः is understood here. Thus णीञ् - नयति, णम - नमति, णह - नह्यति ॥ But not अण् - अणति ॥ This does not apply to roots derived from nouns. णकारमिच्छति = णकारीयात ॥The roots are exhibited in the Dhatupatha with ण् for a similar reason as they are exibited with ष ॥ By 8.4.14, these roots change their न into ण when preceded by certain prepositions. All roots beginning with a ण should be understood to have been so taught, with the exception of the following:- नृ, नन्दि नर्दि, नक्क, नाटि, नाधृ and नाथृ ॥,