This snail's shell is not green.
Instead, the shell is semi-transparent. It's the snail that's green.
Thanks, Nick Crumpton!
Maggie Koerth-Baker is the science editor at BoingBoing.net. She writes a monthly column for The New York Times Magazine and is the author of Before the Lights Go Out, a book about electricity, infrastructure, and the future of energy. You can find Maggie on Twitter and Facebook.