AMCEB^E OF THE INTESTINAL TRACT. 115 



In a collective study of the occurrence of amoebic 

 dysentery in the United States, Patterson records 

 cases reported from Maine, New Hampshire, New 

 York, Pennsylvania, Maryland, District of Columbia, 

 Virginia, West Virginia, North Carolina, South 

 Carolina, Georgia, Florida, Tennessee, Alabama, 

 Mississippi, Ohio, Illinois, Missouri, Michigan, 

 Minnesota, Montana, Arkansas, Indian Territory 

 and Texas. Long has reported numerous cases 

 originating in California and it is very probable that 

 in this State the infection was imported by soldiers 

 returning from the Philippine Islands. 



While the disease is wide-spread in the United 

 States and is probably much more common than is 

 generally supposed, it has nowhere been reported in 

 epidemic form, but occurs as isolated cases in many 

 of which the exact origin of the infection is prob- 

 lematical. Entamoeba histolytica is generally consid- 

 ered as the exciting cause in the infections reported 

 as originating in this country, but unfortunately the 

 species present have not been studied thoroughly 

 and it may be that many of these cases are really due 

 to a distinct species endemic in the United States. 

 I have recently found Entamoeba tetragena in cases 

 originating in the United States as well as Enta- 

 moeba Mstolytica. 



MORPHOLOGY. Like Entamoeba coli this parasite 



