60 PA THOGENIC BA CTERIA. Achard1 studied 49 cases to determine whether or not the intestinal bacteria entered the organism during the death agony. In 14 bacteria were found intra vitam in the liver and in the blood. In 24 no bacteria were found during life, but after death. In n no bacteria were found either during life or after death—before twenty-two to twenty-seven hours, when his autopsies were made. The passage of bacteria into the blood during agony was unusual. The bacteria most commonly found during life were the streptococci and staphylococci. In the dead body the one most frequently encountered was the bacillus coli communis. Before reaching the intestine the bacteria pass through the stomach, and must resist the deleterious action of the acid gastric juice, which few are able to do. (b) The Respiratory Tract.—Notwithstanding the moist interiors of the mouth and nose and the lashing cilia of the pharyngeal and tracheal mucous membrane, numbers of bacteria enter the smaller bronchioles, and occasionally penetrate as deeply as the air-cells. It is usual to find a few bacteria in a section of healthy lung. Thomson and Hewlett2 estimate that from 1500 to 14,000 bacteria are inspired every hour. As expired air is usually sterile, they sought to determine what became of these organisms, and agree with Lister and with Hildebrandt that the organisms are arrested before they reach the air-cells. They found by killing a number of animals and examining the tracheal surface that it was sterile, and conclude that the great majority of bacteria are stopped in the nose against the moist surfaces of its vestibules, where they found great numbers in the crusts. No doubt the ciliated cells of the nose have something to do with getting rid of the bacteria. An ingenious experiment was performed by placing some bacilli prodigiosus upon the septum naris, and making a culture from the spot at intervals during two 1 Archives de medecine exp&rimentale et d'antomie pathologique, 1895, No- I, P. 25. 2 British Mid. Jour., Jan. 18, 1896, p. 137.