530 
M. H. REYNOLDS. 
His experiments on rabbits with anthrax bacilli are well 
worthy of study. He produced an inflammation of one ear 
by applying croton oil, leaving the other untouched. He then 
injected a pure culture of bacillus anthracis, and compared 
results on the two ears. His conclusions are that “ the bacil¬ 
lus of anthrax finds in a soil prepared by an inflammation, in¬ 
duced by croton oil, a locus minoris resistentias, which pre¬ 
sents more favorable conditions for its growth than tissues in 
other parts of the body.” His conclusions may be summar¬ 
ized as follows : “ Localization of pre-existing micro-organisms 
in tissues prepared by injury or disease takes place, provided 
that the necessary conditions for their growth are present.” 
But recent tissue lesions are not the only factors which 
may serve to produce such an area of lessened tissue resist¬ 
ance. The presence of old pathological products, exposure, 
feeble performance of any organic function, and a variety of 
general and illy-defined factors seem to produce conditions 
favorable to local infection. The regions which fistulas usu¬ 
ally select are such as are liable to receive blows and bruises, 
given by angry attendants, received in passing under low 
sheds and through low doors, or while rolling. Again, the 
soft tissues of these parts are mainly connective, and connect¬ 
ive tissue areas are very prone to chronic suppurative proc¬ 
esses and slow healing. Such then are the factors which 
serve to locate suppurative processes. 
Need of Continued Research in this Field. —There 
yet remain n^any questions regarding the history and work 
of pyogenic microbes for bacteriologists and chemists to 
answer. We all wish to' know to what depth beyond the 
surface of a pyogenic membrane do these pus-producing 
germs reach. Why does pus “ burrow ?” Is it by pressure 
and absorption ? Is it due to a peptonizing activity of bac¬ 
terial waste products, or is it due to some mysterious part 
played by the pyogenic microbes in their effect upon proto¬ 
plasmic cell contents ? We do not know so much as we would 
wish regarding the metastatic tendency of suppurative proc¬ 
esses. Fistulas sometimes heal rapidly and abscesses develop 
in the atlo-axoid region. There are some strange features in 
