द्वौ तावृतु: षडयनं दक्षिणं चोत्तरं दिवि ॥ ११ ॥
pitṝṇāṁ tad ahar-niśam
dvau tāv ṛtuḥ ṣaḍ ayanaṁ
dakṣiṇaṁ cottaraṁ divi
tayoḥ — of them; samuccayaḥ — aggregate; māsaḥ — month; pitṝṇām — of the Pitā planets; tat — that (month); ahaḥ-niśam — day and night; dvau — two; tau — months; ṛtuḥ — a season; ṣaṭ — six; ayanam — the movement of the sun in six months; dakṣiṇam — southern; ca — also; uttaram — northern; divi — in the heavens.
The aggregate of two fortnights is one month, and that period is one complete day and night for the Pitā planets. Two of such months comprise one season, and six months comprise one complete movement of the sun from south to north.