INFECTION AND INTOXICA TION. 75 



came of the organisms ; and agree with Lister and Hilde- 

 brandt that the organisms are arrested and killed before 

 they reach the air-cells. They found by killing a num- 

 ber of animals and examining the tracheal surface that it 

 was sterile, and concluded that the great majority of bac- 

 teria are stopped in the nose against the moist surfaces of 

 its vestibules, where they are found in great numbers in 

 the crusts. An ingenious experiment performed con- 

 sisted in placing some Bacilli prodigiosi upon the sep- 

 tum naris and making a culture from the spot at intervals 

 during two hours. Cultures made within five minutes 

 showed confluent colonies of the bacteria, which became 

 fewer and fewer in number until, after two hours, not a 

 bacillus could be found. According to Wurtz and Ler- 

 moyez, the nasal secretions exert a germicidal action, but 

 this observation lacks confirmation. 



That micro-organisms do gain admission to the pul- 

 monary tissue the same as other minute objects, is shown 

 by the experiments of Buchner upon anthrax. Anthrax- 

 spores and lycopodium powder were mixed together and 

 distributed so that animals inhaled them. 



Tuberculosis, pneumonia, small-pox, measles, scarla- 

 tina, and a variety of other infectious diseases probably 

 result in many cases from inhalation of the specific 

 micro-organisms. 



d. Mouth and Digestive Apparatus. — Probably the 

 most important bacteriologic studies of the mouth are 

 those of Miller of Berlin, who has isolated twenty or thirty 

 different species. Of these a few, such as the Lepto- 

 thrix innominata, Bacillus buccalis maximus, Leptothrix 

 buccalis maxima, Iodococcus vaginatus, Spirillum sputi- 

 genum, and Spirochaeta dentinum, are of invariable oc- 

 currence, though all non-pathogenic. Of the pathogenic 

 cocci, the Staphylococcus pyogenes aureus and albus, 

 the pneumococcus, the Streptococcus pyogenes, Micro- 

 coccus tetragenus, and a number of species pathogenic 

 for animals only, have been found by different observers. 

 Considerable difference seems to occur among different 



