fetid vs mephitic

fetid

adj
  • Foul-smelling, stinking. 

noun
  • The foul-smelling asafoetida plant, or its extracts. 

mephitic

adj
  • Foul-smelling or noxious, particularly of a gas or atmosphere. 

How often have the words fetid and mephitic occurred in a corpus of books? (source: Google Ngram Viewer )