The first printing of Spiders has no letter code anywhere. ©Copyright 1968 by Western Publishing Company, Inc. Published by Golden Press, New York. Cover price is $1.00. Number on the spine is 24021. Listed as a Golden Nature Guide. (image #1)
A sixth printing (FG) of Spiders has no price listed anywhere. © 1968. No change in the contents or cover art. Golden Press probably published books without prices so sellers could set their own price. (not shown)
Shown next is a minor cover (text) change to Spiders. The text also changed on the back cover. And one illustration was deleted. Cover price is $1.95. My copy has IJK on page 160. ISBN 0-307-24021-5 on the back cover. Listed as a Golden Guide on the cover and a Golden Nature Guide on the inside front cover.
A completely new cover for Spiders is shown last. Stated on the copyright page: 1990 edition. No cover price. ISBN 0-307-24021-5 on the back cover. My copy has the letters GHIJKL on page 160. This book probably exists in an A edition.
Image #1 also exists in a large (5 ¼ by 7 ¾ inch) hardcover. The number on the back cover is 63542.
No revised edition exists. Still in print by St. Martin's Press.