pellucid vs selfpossessed

pellucid

adj
  • Allowing the passage of light; translucent or transparent. 

  • Easily understood; clear. 

  • Of music or some other sound: not discordant or harsh; clear and pure-sounding. 

  • Of a person, their mind, etc.: able to think and understand clearly; not confused; clear, sharp. 

selfpossessed

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