escolar vs ex-lax fish

escolar

noun
  • Any fish of species Ruvettus pretiosus, oilfish. 

  • Lepidocybium flavobrunneum, one of the snake mackerels. 

  • Any of several other perciform fish of the family Gempylidae (snake mackerels). 

ex-lax fish

noun
  • Synonym of escolar (an oily marine fish with white flesh, reminiscent of, and fraudulently passed off as, tuna) 

How often have the words escolar and ex-lax fish occurred in a corpus of books? (source: Google Ngram Viewer )