AM(EB.E OF THE INTESTINAL TRACT. 79 



tiation becomes of very great importance in the diag- 

 nosis of diarrhoeal conditions of the intestine. 



In order to determine how long infection with 

 Entamceba coli might exist we made the following 

 examinations : 



A. Upon November 20, 1906, thirteen men were 

 re-examined who had been first examined upon 

 March 17, 1906, eight months having elapsed since 

 the first examination. Of these thirteen men, eleven 

 showed Entamosba coli in their feces March 17, and 

 nine or 81.8 per cent, still showed them upon Novem- 

 ber 20. During this time not one of these men had 

 suffered from diarrhoea, and all had been on duty 

 continuously at the hospital. 



B. Upon November 20, 1906, seven men were 

 re-examined who were first examined upon May 2, 

 1906, six months and twenty-two days having elapsed 

 since the first examination. Of these seven men, five 

 were positive for Entamceba coli upon May 2, and 

 five were still positive upon November 20, and none 

 of these men had suffered from diarrhoea or dysentery 

 during this time, and were continuously under ob- 

 servation. 



C. Upon November 20, 1906, eight men were 

 re-examined who were first examined upon July 10, 

 1906, four months and thirteen days having elapsed 

 since the first examination. Of these eight men, five 



