I swear, I must be losing my mind.

I remember a monster list from 2E (maybe in the original 3-ring loose-page MC?), where it listed common monster encounters by terrain, ie these are monsters found in mountainous settings, these are monsters encountered in forest settings, these are found in desert areas, etc.
I want to be able to check a list of monsters commonly found by terrain, ie mountainous, jungle, swamp, etc.
Can anyone tell me where these lists were, and if they have a list post it here? Thanks!