This volume comprises the transactions of the forty-ninth annual session of this Society, held in Lafayette, Ind., May 5 and 6, 1898. In addition to the usual data found in "Transactions," the following papers presented before the Society are printed: "President's Address," "Myths and Medicine," "Cerebral Centers for Pain," "Sudden Blindness," "Trachoma," "Optic Neuritis, Its Relation to Cerebral Disturbances, Toxicity, etc." "Some Points in the Etiology of Typhoid Fever," "Summary of a Report of 100 Cases of Typhoid," "Biology—Its Relations with Medicine as a Factor in Cosmology," "Symptoms, Diagnosis and Treatment of Appendicitis," "Gonorrheal Septicemia," "The Diagnosis of the Different Diseases of the Liver," "Patent Medicines vs. Scientific Medicine," "Spinal Irritation," "Tuberculosis-Prevention and Treatment," "Constipation—Its Causes, Effects and Treatment," "Pneumonia," "Auto-intoxication," "Of What Value is Alcohol as a Medicine?" "Inflammation from a Surgical Point of View," "Chloroform and Ether Narcosis," "Sarcoma of the Kidney in Childhood," "Nasopharyngitis—Its Causes and Treatment,"