Jack-in-the-pulpit vs memory root

Jack-in-the-pulpit

noun
  • A plant in the northeastern North America, Arisaema triphyllum. 

  • Any plant in the genus Arisaema. 

  • Cat's cradle. 

  • A woodland plant of northern Europe, Arum maculatum. 

memory root

noun
  • Synonym of Jack-in-the-pulpit (“the plant Arisaema triphyllum”) 

How often have the words Jack-in-the-pulpit and memory root occurred in a corpus of books? (source: Google Ngram Viewer )