Thomas Bowdler was a famous expurgator.    From Wordnet, Princeton University. 

But when Herman and Verman set to 't the record must be no more than a few fragments left by the expurgator.    From Wordnik.com.  [Penrod] Reference

Whoever he was, he can have little claim to be regarded as the original designer; he was rather employed as an expurgator; for these plates are certainly copies of the two sets of plates invented and engraved by Hogarth himself in 1726.    From Wordnik.com.  [Notes and Queries, Number 52, October 26, 1850 A Medium of Inter-communication for Literary Men, Artists, Antiquaries, Genealogists, etc] Reference