baleen vs dewlap

baleen

noun
  • A baleen whale, 

  • The keratinous material that makes up the plates in the mouth of the baleen whale, Mysticeti, which it uses to trap its food; formerly used in corsetry. 

dewlap

noun
  • The pendulous skin under the neck of an ox, or a similar feature on any other animal. 

  • The sagging flesh on the throat of an elderly human. 

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