|FIRST EDITION IDENTIFIERS:
A.C. McClurg only printed this book one time, which was on March 21, 1925. So any book with "A.C. McClurg & Co"on the spine is a first edition. Notice the cover says "The Cave Girl" and the spine just says "Cave Girl". The dust jacket and frontispiece art are both the same and done by J. Allen St. John. There are no other illustrations.
This is the first book of four separate titles in a row that have blue cloth boards with black lettering. All four of the books are individual books, not part of a series, and published within one year of each other. The print-run of each of the four books was only 5,000 copies making these four among the more difficult books to find. In addition, the blue cloth on the spines of these books tend to darken easily making it difficult to find one that hasn't been sun-damaged.