ङ्णोः कुक्टुक् शरि

The augment क् is added to a final ङ् and the augment ट् to a final ण् before a sibilant, optionally.
Thus प्राङ्क् शेते, or प्राङ् शेते; प्राङ्क् षष्ठः or प्राङ् षष्ठः, प्राङ्क् साये or प्राङ् साये ॥ वण्ट् शेते or वण् शेते ॥

The augments are कुक् and टुक् with an indicatory क्, showing that they are to be added to the end of the prior word 1.1.46, and not to the beginning of the second word. In sanhita reading, it would have made no difference practically, whether these augments were added to the end of the first, or the beginning of the second. But they are added to the end of the first, in order to indicate that 8.4.63, will take effect. Thus we have प्राङ्क् छेते also. This छ change of श would not have taken place had the augment क् been added to श् of शेते; because in शश्छोटि 8.4.63 the झय् letter must be at the end of a pada. So that if क् were added to श of शेते, as क्शेते, here too श follows a झय् letter, but this झय् letter (क्) is not at the end of a pada, so श will not be changed to छ 8.4.63. Thus श is not changed to छ in the body of a word, like विरप्शिन् though प् is a झय् letter. पुरा क्रूरस्य विसृपो विरप्शिन् ॥ विरप्शिन् = महत्, formed with the Preposition वि added to the root रप्, with the Unadi affix शिनि ॥

Moreover in प्राङ्क् साये, the स is not changed to ष by 8.3.59. Had the augment क् been added to साये, as क्साये, the स would have been changed to ष, as प्राङ् क्षाये, for then 8.3.111, would not have applied, as स was no longer at the beginning of a pada.

Moreover in वण्ट् साये, the स् is not changed to ष because of the prohibition of 8.4.42. Had ट् been the augment of साये as ट्साये, then there would have been the change of स् to ष् by 8.4.41.