The American Philosophical Society announces that a prize of $2,000, known as the Henry M. Phillips Prize, will be awarded for an essay on "The Treaty-making Power of the United States and the methods of its enforcement as affecting the Police Powers of the States." All essays must be type-written on one side of the paper only, and must bear an assumed name. All essays must be handed in to the American Philosophical Society, 104 South Fifth street. Philadelphia, Pa., before January 1, 1912.