20 



before. His stools were generally 'watery', but also contained 

 blood and mucus; and numerous amoebae — identified as Enta- 

 moeba histolytica — were present in them. Attempts were made 

 to infect cats with the amoebae, but at the time of writing the 

 result of the experiments was not known. The patient was 

 treated with ipecacuanha, which appears to have benefited him : 

 for though he relapsed after a first course, he was, when the paper 

 was written, ' almost convalescent ' after a second. 



It is uncertain how this patient acquired his infection. 

 Marshall suspected that he might have got it from a soldier, who 

 had been in India, in the same neighbourhood. But this soldier 

 was not proved to be a carrier of E. histolytica. ' Spores ' were 

 present in his stools, ' but whether they were the spores of 

 Entamoeba histolytica could not be determined by mere micro- 

 scopic examination '. 



It appears probable that Marshall's case was also one of 

 E. histolytica infection, though the published evidence is not 

 wholly satisfactory. The author appears to have held peculiar 

 views regarding the life-history of E. histolytica ; and from his 

 •description and figures it is, unfortunately, impossible to identify 

 the organisms with which he was dealing. Corroborative evi- 

 dence from animal experiments and emetine treatment is also — 

 as already implied — lacking. 



There are other cases of possibly indigenous E. histolytica 

 infection on record, but as they all appear doubtful as ' British ' 

 ■cases, I shall not consider them here. It is possible, however, 

 that some of them were really indigenous. The case of Bassett- 

 Smith (1900) will serve as an instance of these doubtful cases, 

 and illustrates the difficulties of interpretation. His patient, 

 a petty officer in the Navy, had been abroad, but had never pre- 

 viously suffered from dysentery. More than two years after 

 returning home to Portsmouth he had an attack of dysentery, 

 followed by the formation of abscesses in the liver and lung. 

 The pus from the former was bacteriologically sterile, but con- 

 tained active forms of ' the amoeba coli '. The disease ultimately 

 proved fatal. It seems clear that this was a case of E. histolytica 

 infection ; but there is no evidence to show where or when the 

 patient originally became infected. He may have acquired his 

 infection whilst abroad, and have remained a contact carrier of 

 the parasite until his fatal illness developed. On the other hand, 

 in the absence of evidence to the contrary, it is possible that he 

 contracted his infection in England — either before he went 

 abroad or at any time after his return. 



As it is impossible to determine the facts with certainty, I have 

 excluded several other doubtful cases, of a similar type, from the 

 present chapter. 



