Two “stolen” notebooks that once belonged to English naturalist Charles Darwin have been returned to Cambridge University, 22 years after they were last seen. The notebooks were wrapped in plastic and left in a bright pink gift bag. There was no clue as to who returned the books, just a printed short message on a brown envelope inside the bag that read: “Librarian, Happy Easter X.” The items – in which Darwin mapped out his theory of evolution about the origin of life – were found to be missing in 2001 during a routine check. It took five days before the notebooks were confirmed to be real. “I feel joyous,” the university’s librarian Dr. Jessica Gardner says. The Cambridgeshire Police are still working on the case.