beefsteak mushroom vs brain mushroom

beefsteak mushroom

noun
  • Gyromitra esculenta (a potentially fatally poisonous fungus that is a delicacy) 

  • Fistulina hepatica (an edible fungus) 

brain mushroom

noun
  • A fungus common in Europe and North America and one of several species of fungi known as false morels, especially Gyromitra esculenta. 

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