The ecliptic is divided into nine divisions known as Vīthis (paths), According to some each division consists of three constellations beginning from Aśvini: these divisions are technically known as—1. Nāga (serpent), 2. Gaja (elephant), 3. Airāvata (the divine elephant), 4. Vṛṣabha (bull), 5. Go (cow), 6. Jaradgava, 7. Mṛga (deer), 8. Aja (ram), 9. Dahana (fire).
According to others the Nāga Vīthi consists of the constellations of Svāti, Bharaṇī and Kṛttikā; the Gaja Vīthi of the three constellations from Rohiṇī; the Airāvata Vīthi of the three from Punaravasu; the Vṛṣabha Vīthi of the three from Māgha; the Go Vīthi of the three from Aśvini Revatī, Pūrvabhādrapada and Uttarabhādrapada.
The Jaradgava Vīthi consists of the three constellations from Śravaṇa; the Mṛga Vīthi of the three from Anurādhā; the Aja Vīthi of Hasta, Viśākhā and Citrā; and the Dahana Vīthi consists of the two constellations Pūrvāṣāḍha and Uttarāṣāḍha.
Of the nine Vīthis the first three are known as the northern Vīthis; the next three as the central Vīthis and the last three as the southern Vīthis. Again in the case of each three the first is known as the northern Vīthi, the second as the central Vīthi and the last as the southern Vīthi.
वीथीमार्गानपरे कथयन्ति यथास्थितान्भमार्गस्य । नक्षत्राणां तारा याम्योत्तरमध्यमास्तद्वत् ॥ ९-०५ ॥
According to some the position of a Vīthi follows that of the Yoga Tārā (chief star) of the particular constellation; so that if the star should be on the north of the ecliptic, the Vīthi is known as the northern one; if on the ecliptic, it is known as the central one and if on the south of the ecliptic, it is known as the southern one.