There is luk elision of the yuvan gotra (Patronymic) forming affix -- jīvati tu vaṃśye yuvā [[4.1.163]], when a prāgdīvyatīya affix beginning with a vowel is to be added.,
The elision of the Yuvan affix must take place mentally; having done which, we should then look out for the proper Pragdivyatiya affix to be added to the word-form thus remaining. Thus the Patronymic (¬Gotra) of फाण्टाहृतः is फाण्टाहृतिः 4.1.95 formed by adding इञ् ॥ The Yuvan form of the latter (by Sutra 4.1.150) will be फाण्टाहृतः ॥ When we intend to add a Pragdivyatiya affix to this last word, (e. g. an affix having the sense of \the pupils of\;) we should first mentally elide the Yuvan affix ण 4.1.150 from this word फाण्टाहृत ॥ Having done which we get the form फाण्टाहृति; and it is with regard to this form फाण्टाहृति that we should search out what is the proper pupil-denoting affix: and that by sutra 4.2.112 is अण् ॥ Thus फाण्टाहृति + अण् = फाण्टाहृताः 'the pupils of Phantahritas'. Had we in the first instance applied the pupil denoting affix to the Yuvan word फाण्टाहृत, such affix would have been छ and not अण्, for the latter is ordained for those cases only where the word ends with the Gotra affix इञ् 4.2.112.
Similarly the Patronymic of भागवित्त is भागवित्ति 4.1.25. The Yuvan of भागवित्ति is भागवित्तिकः 4.1.148. The pupils of Bhagavittika will be भागवित्ताः by adding the affix अण् 4.2.112.
Similarly the Patronymic of तिक is तैकायनि formed by फिञ् 4.1.154. The Yuvan of तैकायनि is तैकायनीय formed by the affix छ 4.1.149. The word denoting the pupils of तैकायनीय will be formed by adding छ 4.2.114 not to this word, but to तैकायनि ॥ Thus तैकायनीयाः ॥
Similarly the Patronymic of कपिञ्जलाद is कपिञ्जलादिः 4.1.95. The Yuvan derivative of the latter will be कापिञ्जलाद्य; (IV. I. 151). The word denoting pupils of the कापिञ्जलाद्य will be कापिञ्जलादाः 4.2.112.
Similarly Patronymic from ग्लुचुक is ग्लुचुकायनिः 4.1.160, the Yuvan of the latter is ग्लौचुकायनः 4.1.83; the word denoting the pupils of the latter is ग्लौचुकायनाः by (IV. 2. 112 formed from ग्लुचुकायनि) ॥ Why do we say \an affix beginning with a vowel\? Observe फाण्टाहृतरूप्यम् and फाण्टाहृतमयम् ॥ Why do we say \a Pragdivyatiya affix\? Observe भागवित्तिकाय हितं = भागावित्तीयम् ॥ (See the last Sutra).,
