268 The Philippine Journal of Science wis 



and had not been used previously for feeding experiments. Physical exami- 

 nation of his abdomen and microscopic and cultural examinations of his 

 stools for amoeboid organisms were negative. He ingested the growth on 

 2 Petri-plate cultures of Aviceba 2A, isolated in culture from the Manila 

 water supply, mixed with magnesium oxide. These cultures contained 

 both motile and encysted amoebae. Transplant cultures made to test the 

 viability of the organisms showed a luxuriant growth of Amceba A. This 

 man was under observation eleven and one-fourth months after the experi- 

 ment began. Following the feeding, cultures of this man's stools on Mus- 

 grave and Clegg's medium and microscopic examination of his stools for 

 amoeboid organisms were constantly negative. No symptoms of dysentery 

 have developed. 



Experiment III. — Man 3, aged 31 years, had been under observation in 

 the prison for six years. He gave a history of one attack of dysentery of 

 one month's duration sixteen years ago. He had been previously used for 

 another feeding experiment with negative results (see experiment I). 

 Physical examination of his abdomen and microscopic and cultural exami- 

 nations of his stools for amoebse were negative. He ingested the growth on 4 

 Petri-plate cultures of Ami£ba I A, isolated from the Manila water supply, 

 mixed with magnesium oxide. The cultures ingested by this man were old 

 ones containing only encysted amoebae. Transplant cultures to test the 

 viability of the cysts gave a luxuriant growth of Amoeba A. This man has 

 been under observation two years and six months since the experiment 

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

 repeated microscopic examinations of his stools for amoeboid organisms 

 have been negative. No symptoms of dysentery have developed. 



Experiment IV. — Man 4, aged 34 years, had been under observation in 

 the prison one year and six months. He had a negative dysenteric his- 

 tory. He had been used previously for another feeding experiment with 

 negative results (see experiment II). Physical examination of the abdomen 

 and cultural and microscopical examinations of his stools for amoeboid organ- 

 isms were negative. He ingested the growth on 4 Petri-plate cultures of 

 Amceba 2 A, isolated from the Manila water supply, mixed with magnesium 

 oxide. The cultures ingested contained both motile and encysted amoebae. 

 This man has been under observation eleven months and seven days since 

 the experiment began, during which time A7n<jeba A has never been found 

 in his stools nor have dysenteric symptoms developed. 



Experiment V. — 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 for another experiment sixty-nine days previously with 

 negative results (see experiment VII). Physical examination of his abdo- 

 men and microscopic and cultural examinations of his stools for amoeboid 

 organisms were negative. He ingested the growth on 4 Petri-plate cul- 

 tures of Amoeba 2A, isolated from the Manila water supply, mixed with 

 magnesium oxide. The cultures fed to this man contained encysted amoebae 

 only. Transplant cultures to test the viability of the cysts showed an 

 abundant growth of Amceba A. This man has been under observation 

 two years and four and one-half months since this experiment began. 

 Cultures and microscopic examinations of his stools for amoeboid organ- 

 isms have been constantly negative, and no symptoms of dysentery have 

 developed. 



