The Metal Monster

According to Stefan Dziemianowicz in the introduction to the Hippocampus Press edition:
The Hippocampus Press edition follows the text of the original serial publication.
The serial version in "Science and Invention" is at least 20% shorter.
The version for the "Famous Fantastic Mysteries" appearance was revised by Merritt and is about 10% shorter than the serial version. This is Merritt's preferred text. Most subsequent book publications are based upon this version.

• "Copyright, 1946, by Avon Book Company."
• Copyright page states "Revised Version" and an associated copyright date of 1941 by Frank A. Munsey Company. So this follows the revision from Famous Fantastic Mysteries August 1941.
• First Avon printing; date from the fifth printing.
• Cover artist uncredited, no visible signature. Cover artist from AbeBooks.
• Price not explicitly stated, but ads on back cover list current releases in this series at 25c.