‘Psychedelics’ book returned to library 37 years late as mysterious note apologizes for ‘long, strange trip’

The librarians weren’t hallucinating.

An anonymous and absent-minded patron finally got around to returning a long-lost book aptly titled “Psychedelics” to a Colorado library nearly 37 years after it was checked out.

“Sorry so late!!” a note stuffed into the book said. “It’s been a long strange trip!!”

Officials at the High Plains Library District in Greeley said the book was due back on May 30, 1987.

“Guns N Roses was still a couple of months away from releasing “Appetite for Destruction” on the day this book was due,” the library wrote in a Facebook post. “Lionel Messi was born two months after it was due.

“Now… far be it from us to suggest that a book on psychedelics may, MAY, have affected someone’s perception of time,” the post said. “But according to a note left in the book, ‘It’s been a long, strange trip.’”

A spokesman at the library told The Post that they stopped charging late fees in 2015, but under the previous rule, the delinquent reader would’ve been slapped with a bill of $1,343.

That’s 10 cents for each of the 13,437 days — 36 years, nine months and 13 days — that the book was off the shelves.

Besides, the library has no clue who snuck in and returned the book, which was written by Bernard Aaronson and Humphry Osmond and published in 1970.

The library, obviously taking the whole thing tongue-in-cheek, said it’s even open to someone breaking the Psychedelic record someday.

“If anyone can beat the current record of 13,437 days, I’m offering you total amnesty for the safe return of your items,” they said on Facebook. “Although I’m not encouraging you to check something out TODAY and return late enough to bear the record, which would be…January 1st, 2061.

“We’ll be closed New Year’s Day. Probably. Maybe. By 2061, who knows?”