OF THE ALIAIENTARY TRACT 25 



site of swine, which is occasionally transmitted to 

 man by swallowing materials contaminated with 

 fecal matter from this animal. The means of pre- 

 vention of such infection by those who may be 

 exposed to it in handling hogs is evident. 



The latter is Endamoeha histolytica, which has 

 been shown by the writer and others to be capable 

 of transmission to and parasitism in the common wild 

 rat. If such should be the case in nature this is 

 potentially a source of spread of the parasite, and the 

 control of the rat, prevention of contamination of 

 food by the excreta of it, and protection of human 

 excreta from this animal, would be necessary to pre- 

 vent such a manner of spread. It seems possible at 

 the present wTiting that in regions where human 

 excreta are exposed to rats which also have access 

 to food of man, this natural means of transmission 

 of this important parasite may occur. It is of suf- 

 ficient importance to demand attention until proven 

 or disproven, at any rate. More recently Kessel 

 (1928) has found an amoeba, identified as Endam- 

 oeba histolytica, in naturally infected pigs in Peking, 

 China, and has, also, brought about experimental 

 infection of this animal by Endavioeha histolytica for 

 a period of about six weeks. The pig is thus, also, 

 accused of serving as a natural carrier of this amoeba 

 and, if so, needs be guarded against in places where 

 such an opportunity may be given it. 



The transmission of these parasites, then, depends 

 upon their natural habits of life, in relation to those 



