Venus' comb vs black jack

Venus' comb

noun
  • An umbelliferous plant, Scandix pecten-veneris. 

black jack

noun
  • Sphalerite. 

  • Caranx lugubris, a gamefish 

  • Bidens spp., from the family of Asteraceae 

How often have the words Venus' comb and black jack occurred in a corpus of books? (source: Google Ngram Viewer )