diff --git a/src/epub/content.opf b/src/epub/content.opf
index 9da8683..699339f 100644
--- a/src/epub/content.opf
+++ b/src/epub/content.opf
@@ -57,7 +57,7 @@
https://www.gutenberg.org/ebooks/2009
https://catalog.hathitrust.org/Record/100424049
Leading chapter summaries in the original have been removed as they merely list the subheadings already in the table of contents.
- 200099
+ 200096
36.56
https://en.wikipedia.org/wiki/The_Origin_of_Species
https://github.com/standardebooks/charles-darwin_the-origin-of-species