cowfish vs eel gudgeon

cowfish

noun
  • A marine plectognath fish, Acanthostracion quadricornis and allied species, having two projections, like horns, in front. 

  • The grampus, Grampus griseus, Risso's dolphin. 

  • A common galaxias (Galaxias maculatus) 

  • Any of genera Acanthostracion and Lactoria, of the boxfish family Ostraciidae. 

  • A common bottlenose dolphin of California, Tursiops truncatus gillii. 

eel gudgeon

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