Captain Jack Butterworth was a human male who commanded the USS Verne in the 24th century. In 2377, he volunteered his ship to assist Captain Saavik and the fleet she had assembled to face the Watraii threat. He was killed in the opening battle with the Watraii vessels. (TOS - Vulcan's Soul novel: Exodus) It is unknown whether this is the same Captain Butterworth referenced in TNG - The Brave and the Bold, Book Two novella: The Final Artifact.