caterpillar vs stick insect

caterpillar

noun
  • The larva of a butterfly or moth; leafworm 

  • A vehicle with a caterpillar track; a crawler 

  • A set of subtrees of a tree 

stick insect

noun
  • Any of various insects of the order Phasmida that mimic sticks or twigs. 

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