Hottentot's god vs mantis

Hottentot's god

noun
  • Synonym of praying mantis 

mantis

noun
  • A green colour, like that of many mantises. 

  • Any of various large insects of the order Mantodea that catch insects or other small animals with their powerful forelegs. 

How often have the words Hottentot's god and mantis occurred in a corpus of books? (source: Google Ngram Viewer )