"Brahma's World" Refers to the Principal Bronchus

 

  Malyavan extends for 1050 yojanas. Men who are born there have the complexion of gold. They have all been dislodged from Brahma’s world and are knowledgeable about the brahman  […] For the sake of protecting beings, they enter the sun. There are 66,000 of them. They surround the sun and travel ahead of the sun. Having been heated by the sun for 66,000 years, they enter the lunar circle.

"Brahma's world" refers to the principal bronchus (Mount Meru). The neural entities ("men") that emanate from the nerve trunk of the principal bronchus and proceed to the lower bronchi have been dislodged, as it were, from "Brahma's world." The neuronal beings in the Puranas represent the intelligent minds of the external world (that operate on matter) and as they are endowed with "intelligence" they are presented as "shining" or "golden." For the sake of "protecting" (innervating), they enter the lobar bronchus – the "sun" or the "chariot of the sun," more specifically [they "travel" in the chariot] – which is positioned just below the primary bronchus (Brahma's world). The Puranics seem to have followed a model in which the neural entities first drop  into the "sun" and from there, split to the other structures in the interior of the lung. For they say that after remaining in close proximity to the sun, these beings proceed to the "lunar circle" which, undoubtedly, is the sphere of the pulmonary veins.