auricle vs auricula

auricle

noun
  • The outer ear or pinna. 

  • Synonym of atrium. 

  • An anterior ear-shaped appendage of the left or right atrium of the human heart. 

  • Any appendage in the shape of an ear or earlobe. 

auricula

noun
  • The external part of the ear. 

  • The ornamental primrose Primula auricula 

  • A small conical pouch projecting from either atrium of the heart. 

  • A pronounced thickening at the corner of a trilete spore, beyond the end of the laesura. 

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