coachwhip vs cow's lungwort

coachwhip

noun
  • Fouquieria splendens (ocotillo). 

  • A long whip used by the driver of a horse-drawn coach. 

  • Masticophis flagellum, a colubrid snake of North America. 

cow's lungwort

noun
  • mullein (Verbascum thapsus) 

How often have the words coachwhip and cow's lungwort occurred in a corpus of books? (source: Google Ngram Viewer )