Ashtangasamgraha 41.23

41.23

brāhmaṇāḥ krodhanā nīlakapilāḥ śvetalohitāḥ |

raktāsyāḥ piṅganayanā medhyadeśavicāriṇaḥ ||

Brāhmaṇa [snakes] are wrathful, dark-blue and tawny, or white and red, / red-mouthed, tawny-eyed, and roam in clean places;