In a preliminary report in 1910, Dr. Ralph H. Spangler1reported the results of the treatment of eleven eases of epilepsy by injections with a solution of the venom of the rattlesnake (Crotalus horridus). In a second paper2he reported on fifty-one additional cases treated with rattlesnake venom. Since then there have appeared reports from others on the use of solutions of crotalin for the treatment not only of epilepsy, but also of certain other conditions, including tuberculosis, all based on purely empiric grounds. I shall not discuss at this time whether or not rattlesnake venom is a cure for epilepsy, nor shall I enter into an analysis of the reported effect on the course of the disease of the venom treatment; but I think it proper to state that it hardly seems permissible to conclude from the published reports that the treatment was of any very great