"The List" refers to the official list that the Appalachian Mountain Club keeps of the 4000-foot peaks. As the mountains are resurveyed over the years, one mountain may suddenly be discovered to be on the list (as was Bondcliff a few years ago) and the lucky climber who has happened to have already been there suddenly has another summit bagged. Alas, it works in reverse too; a new survey may shrink a mountain and make it vanish from the list -- and thus from the climber's accomplishments.