The seven islands are mentioned in the Siddhāntaśiromaṇi: bhūmer ardhaṁ kṣāra-sindhor udak-sthaṁ jambu-dvīpaṁ prāhur ācārya-varyāḥardhe ’nyasmin dvīpa-ṣaṭkasya yāmye kṣāra-kṣīrādy-ambudhīnāṁ niveśaḥ śākaṁ tataḥ śālmalam atra kauśaṁ krauñcaṁ ca gomedaka-puṣkare cadvayor dvayor antaram ekam ekaṁ samudrayor dvīpam udāharanti The seven islands (dvīpas) are known as (1) Jambu, (2) Śāka, (3) Śālmalī, (4) Kuśa, (5) Krauñca, (6) Gomeda, or Plakṣa, and (7) Puṣkara. The planets are called dvīpas. Outer space is like an ocean of air. Just as there are islands in the watery ocean, these planets in the ocean of space are called dvīpas, or islands in outer space. There are nine khaṇḍas, known as (1) Bhārata, (2) Kinnara, (3) Hari, (4) Kuru, (5) Hiraṇmaya, (6) Ramyaka, (7) Ilāvṛta, (8) Bhadrāśva and (9) Ketumāla. These are different parts of Jambudvīpa. A valley between two mountains is called a khaṇḍa or varṣa.