CASE.—Private William A. H——, Co. E, 19th Indiana Volunteers, aged 21 years, was wounded at the battle of Antietam, Maryland, September 17th, 1862, by a conoidal ball, which fractured and depressed both tables of the anterior inferior portion of the right parietal bone. The missile had split upon the fractured edge of the bone. He was conveyed to Washington, and admitted to the Capitol Hospital on the 23d, and was thence transferred to the Satterlee Hospital, Philadelphia, October 12th. Three days later, Assistant Surgeon E. de W. Breneman, U. S. A., made a semi-lunar incision in the scalp, and dissected up the flap, when a copious hæmorrhage occurred. He then removed several small detached pieces of bone, and also a triangular piece of the internal table, which was pressing heavily upon the dura mater, and by means of an elevator, raised an adjacent portion of the bone. The membranes of the brain were found to be penetrated, and from the character of the discharge, it was believed that the brain itself was seriously injured. The pulsations of the middle meningeal artery were distinctly felt. After the operation the symptoms of compression passed away. The patient was much prostrated, but in the full possession of his senses. He was kept in bed, on low diet, and under antiphlogistic treatment. On October 23d he was attacked with colliquative diarrhœa. Pyæmia supervened, causing death on the 21st of November, 1862. The pathological specimen, No. 883, Sect. I, A. M. M., shows five small fragments, from both tables of the parietal bone, representing nearly one square inch of surface. The specimen and history were contributed by Assistant Surgeon E. de W. Breneman, U. S. A.