Matsya Purana — Navagraha Sacrifice for Planetary Pacification and Prosperity
गजौष्ठसदृशी तद्वद् आयता छिद्रसंयुता एतत्सर्वेषु कुण्डेषु योनिलक्षणमुच्यते //
gajauṣṭhasadṛśī tadvad āyatā chidrasaṃyutā etatsarveṣu kuṇḍeṣu yonilakṣaṇamucyate //
Resembling an elephant’s lip, likewise elongated and furnished with an aperture—this is declared to be the defining “yoni” mark in all kinds of ritual fire-pits (kuṇḍas).
This verse is not about Pralaya; it is a technical Vastu-ritual rule describing the standard “yoni” feature (an outlet-like mark) used in the construction of yajña fire-pits.
It supports dharmic duty by prescribing correct ritual infrastructure: a king or householder sponsoring yajñas should ensure the kuṇḍa is built with the proper yoni-lakṣaṇa so rites are performed according to śāstra.
It defines the yoni-lakṣaṇa for all kuṇḍas: an elephant-lip-like, elongated form with an opening, indicating a standardized outlet/feature essential to proper kunda geometry in ritual practice.