house martin vs western fence lizard

house martin

noun
  • A migratory passerine bird of the swallow family, genus Delichon 

  • The common house martin (Delichon urbicum). 

western fence lizard

noun
  • Sceloporus occidentalis, a North American lizard. 

How often have the words house martin and western fence lizard occurred in a corpus of books? (source: Google Ngram Viewer )