उपधायां च

The anuvritti of हलि is current. The root must end in a consonant, and must have a र् or व् as preceding such consonant, for the application of this rule. Thus हूर्छा, हूर्छिता, मूर्छा, मूर्छिता, तूर्वी, तूर्विता, धूर्वी, धूर्विता ॥

The र् or व् must be followed by a consonant. Therefore not here: as, चिरि, जिरि are roots having a penultimate र, which however is followed by a vowel. Therefore we have चिरिणोति, जिरिणोति ॥

Question:- Why there is not lengthening in रिर्यतुः, रिर्युः or विव्यतुः, विव्युः Perfect, forms derived from the roots रि गतौ and वी गतौ &c? Here the इ of the abhyasa required lengthening, and it would not be shortened, as it is asiddha.

Answer:- The यण् substitute of इ here by 6.4.82, is treated as sthanivat, to इ, and therefore, the र् or व् is considered as not to be followed by a consonant, and hence there is no lengthening. Another reason is, that the यण् substitute is taught in angadhikara 6.4.82, and depends upon the affix, and is consequently Bahiranga, with regard to this rule of lengthening which is antaranga. Hence यणादेशः is considered as asiddha. Therefore र् and व् are not followed by a consonant (for य् is not considered as such for the above reasons).

Similarly in चतुर्यितृ formed with तृच् affix from the Denominative (क्यच्) root चतुर्य ॥ Here इट् is added before तृच् as चतुर्य + इ + तृ and then अ is elided, चतुर्य् + इ + तृ ॥ Here the elision of अ is a Bahiranga process, and therefore, र् is not here really penultimate, and so there is no lengthening of the vowel.

In प्रतिदीव्ना (Instrumental singular) there is lengthening by 8.2.77. To the root प्रति-दिव् is added कनिन् by Unadi I. 156, and we have प्रतिदिवन् ॥ To this is added टा (Instrumental affix), as प्रतिदिवन् + आ, and अ is elided by 6.4.134, and we get प्रतिदीव्ना ॥ The lengthening takes place here, the elision of अ is not considered here as sthanivat, and so व् becomes penultimate. In fact, here we apply the maxim that a lopa substitute of a vowel is not to be considered as sthanivat when a rule of lengthening is to be applied (See 1.1.58).

Question:- Well, let it not be sthanivat, but the elision by 6.4.134, depends upon a case-affix, and is Bahiranga, and therefore asiddha for the purposes of this rule which is antaranga: and so therefore, there would be no lengthening?

Answer:- The maxim of असिद्ध बहिरङ्गमन्तरङ्ग should not be applied here: because it is an anitya rule.

The word जिव्रिः is formed by the Unadi affix क्रिन् added to the root वॄ (जिर्), the र् being changed to व (Unadi V. 49). So also किरिः and गिरिः are formed by the Unadi affix कि added to कॄ and गॄ (Unadi IV. 143). The Genitive Dual of which is किर्योः and गिर्योः ॥ There is no lengthening in जिव्रिः, किर्योः and गिर्योः, on the maxim that the Unadi formed words are primitive words and not Derivative; and so the rules of etymological changes do not apply to them (उणादयोऽव्युत्पन्नानि प्रातिपदिकानि) ॥,