āstṛta-āyāma - the length and breadth; mārgaḥ ayam - a broad way; rasanām - the tongue; pratigarjati - resembles; eṣām antaḥ-gatam - on the inside of the mountains; dhvāntam - darkness; etat - this; api - indeed; antaḥ-ānanam - the inside of the mouth.

In length and breadth the animal’s tongue resembles a broad traffic-way, and the inside of its mouth is very, very dark, like a cave in a mountain.