armorial bearing vs logotype

armorial bearing

noun
  • Heraldry that consists of a design or image depicted on a shield 

logotype

noun
  • A symbol or emblem that acts as a trademark or a means of identification of an institution or other entity, usually referred to as a logo. 

  • A single type combining two or more letters (as a ligature or otherwise). 

How often have the words armorial bearing and logotype occurred in a corpus of books? (source: Google Ngram Viewer )