celery vs dog's tongue

celery

noun
  • The stalks of this herb eaten as a vegetable. 

  • A European herb (Apium graveolens) of the carrot family. 

  • A yellow-green colour, like that of a celery. 

dog's tongue

noun
  • The plant hound's tongue. 

How often have the words celery and dog's tongue occurred in a corpus of books? (source: Google Ngram Viewer )