It’s a modern version of a dark fable involving a hare, a turtle and a fox. Maine Audubon is seeking three “invaluable” exhibit items that were stolen last weekend from its wildlife education collection: a snowshoe hare and a pond turtle, each preserved by a taxidermist and mounted in a Plexiglas box, and a red fox pelt. The display pieces were taken this week from an Audubon instructor’s locked vehicle while it was parked in a Portland parking garage.