292 The Philippine Journal of Science wis 



controlled by microscopic examination of the stools until each 

 man was cured. 



Complete protocols of each man are given in order to put 

 on record the details of these experiments. 



ENTAMOEBA HISTOLYTICA, STRAIN A, FIRST PASSAGE 



Strain A of Entamoeba histolytica was from a man conva- 

 lescent from a slight attack of entamoebic dysentery of two days' 

 duration. This man had been convalescent from fifty-nine to 

 one hundred sixty-one days when the entamoebas from his stools 

 were used for these feeding experiments, and he has not sub- 

 sequently suffered a relapse of the dysentery. His formed 

 stools contained many cysts of Entamoeba histolytica. This 

 strain was ingested by 3 men and carried by subsequent pas- 

 sages through 9 other men. 



Experiment XLI. — Man 2, aged 40 years, had been under observation 

 in the prison five years and one month. He had a negative dysenteric 

 history. He had been used previously for 2 feeding experiments with 

 cultures of amoebas, ninety-six and seventeen days previously, both of which 

 were negative (part II, experiments VII and V). Physical examination 

 of his abdomen and cultural and microscopic examinations of his stools for 

 amoeboid organisms were negative. He ingested cysts of Entamoeba histo- 

 lytica, strain A, mixed with magnesium oxide. This man received a saline 

 purgative by mistake in the evening of the day that he ingested the infectious 

 material. He became parasitized with Entamoeba histolytica, the encysted 

 entamoebae appearing in his stools on the eleventh day. Cultures of his 

 stools on Musgrave and Clegg's medium were negative. On the twentieth 

 day he developed an attack of dysentery with bloody mucous stools contain- 

 ing motile Entam,ceba histolytica, many of which were filled with red blood 

 corpuscles. Physical examination disclosed pain over the abdomen, no 

 tenderness except over the sigmoid and caecum, sigmoid not palpable, and 

 liver dulness normal. He was put on ipecac treatment, and on the thirtieth 

 day all symptoms of dysentery had disappeared. Encysted Entamoeba his- 

 tolytica, however, continued to be present in his stools. On the seventieth 

 day there was a relapse of the dysentery with motile entamoebse in the bloody 

 mucous stools. Cultures of his stools on Musgrave and Clegg's medium were 

 again negative. The patient was again put on ipecac treatment, the 

 symptoms soon abated, and, up to the present time, he has suffered no 

 further relapse, but encysted entamoeba soon reappeared in his stools and 

 have persisted ever since. He has been under observation for one year 

 since the beginning of this experiment. 



Experiment XLII. — Man 29, aged 35 years, had been under observation 

 in the prison for seven years and ten months. He had not been used pre- 

 viously for experiments, and had no history of dysentery. Physical 

 examination of his abdomen and cultural and microscopic examinations 

 of his stools for amoeboid organisms were negative. He ingested 

 cysts of Entamoeba histolytica, strain A, mixed with magnesium 

 oxide. Following the ingestion, both cultures and microscopic examina- 

 tion of the stools of man 2 were negative. Therefore, this man failed to 



