The Thing on the Bike Path

From the introduction:

It was like something out of those spooky books by that old Maine horror writer. People had been disappearing off the University of Maine bike trail, and only pieces of them had turned up later. The police thought it might have been bears, since there have been some bear attacks in the Maine woods recently. But I know bears, and bears don’t do stuff like was done to the bodies. It was something else, something from a long time ago...