A stolen diamond is hidden by sticking it to the skeleton of a triceratops in the Museum of Natural History.
This is actually the first of the Larry mysteries, and is reasonably good. Unfortunately, the alternate title, under which Boy’s Life first published it telegraphs the solution rather badly—and I happened to be a subscriber to Boy’s Life at the time the story appeared. Still, it would be fine for its intended audience.
|The Key Word and Other Mysteries|