allis shad vs herring

allis shad

noun
  • A herring-like fish (Alosa alosa), of the eastern Atlantic that migrates to fresh water to spawn. 

herring

noun
  • Fish in the family Clupeidae. 

  • A type of small, oily fish of the genus Clupea, often used as food. 

  • Fish similar to those in genus Clupea, many of those in the order Clupeiformes. 

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