The *content* of the reprint--the original text & artwork--is in the public domain. The *layout and formatting* are copyrighted, along with an additional material (annotations, new artwork, etc.)
The issue of how much copyright protects formatting hasn't come up in court. Plenty of publishers release new editions of public-domain materials with dire warnings about copyright infringement; so far, nobody's rounded up those materials, stripped out the new content, and resold them, which is what it'd take to trigger a definitive court case.
If you had a way to get the complete scans of the reprinted version, and OCR'd them, and removed the new material, it could be released as a public domain ebook.