fauna vs zoology

fauna

noun
  • Animals considered as a group; especially those of a particular country, region, time. 

  • A book, cataloguing the animals of a country. 

zoology

noun
  • The part of biology relating to the animal kingdom, including the structure, embryology, evolution, classification, habits, and distribution of all animals, both living and extinct. 

  • A treatise on this science. 

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