embryonal vs rudimentary

embryonal

adj

  • embryonic 

rudimentary

adj

  • Basic; minimal; with less than, or only the minimum, necessary. 

  • Of or relating to one or more rudiments. 

noun

  • One of the rudimentary mammae of boars. 

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