इदितो नुम् धातोः

न् is added after the vowel of a root in a root which has an indicatory इ in the धातुपाठ।
Thus from कुडि — कुण्डितृ, कुण्डितुम्, कुण्डितव्यम्; from हुडि — हुण्डितृ, हुण्डितुम्, हुण्डितव्यम् &c. But पचति, पठति where इ is not इत् ॥ The न् is added to the root from its very inception, and they must be considered to have got a न, for the purposes of the application of the grammatical rules. Thus 3.3.103 says that आ is added in the feminine to a root which ends in a consonant and has a prosodially long vowel. The root कुडि must be considered to be such a root and कुण्डा, हुण्डा are thus formed. Similarly though the roots in the Dhatupatha are धिवि and कृवि, in applying affixes we must consider them as धिन्व् and कृन्व्, as the author himself has indicated in 3.1.80. In short, in adding affixes, these roots should be considered as having न् ॥ Moreover the root (dhatu) should have इ, and not the stem (anga). The affixes तासि (Future) and सिच् (Aorist) when added to roots, will not make those roots इदित्; for the इ in तासि and सिच् is merely for the sake of pronunciation, and is not to be considered as इत् in the strict sense of the word: in fact it should be considered as non-nasalised. If you say that "the इ in सिच् should be considered as इत्, for because of its being इत्, the न् of मन् is not elided by 6.4.24 in अमंस्ता", we reply, "not so, the न् is not elided, because sutra हनः सिच् (1.2. 14) makes सिच् a कित् after हन् only, the result of which is that हन् only loses its न् by 6.4.37, and no other root". In मन्ता = मन् + तासि + डा = मन् + त् + आ (the आस् is elided 6.4.143). For the purposes of the elision of न्, the elided आस् would be considered as asiddha 6.4.22, for both 6.4.143, and 6.4.37, requiring the elision of न् are abhiya sutras. In भेत्ता, छेत्ता from भिदिर् and छिदिर् the whole combination इर् is इत्, and not इ and र् separately, and hence नुम् is not added. But even if these roots be considered as इदित्, the syllable इर् having an इ, yet they will not get the नुम् augment, because the word अन्त of पादान्ते 7.1.57 is understood here in this sutra also, so that the roots must have a final इ as इत् for the application of this rule.