Perforation of the large intestine is not rare, Strong having noted 12 perforations in 77 autopsies. These usually occur in the region of the sigmoid flexure. Adhesions are common complications of amoebic dysentery. DIAGNOSIS =Clinical Diagnosis.=—In the clinical diagnosis it is well to remember that many cases of chronic tropical diarrhoeas are really due to amoebic ulcerations of the intestines. We can as a rule differentiate bacillary from amoebic dysentery by the more sudden and acute onset of the former together with fever and other evidences of toxaemia. The pulse rate is more rapid in bacillary than amoebic dysentery. Again the number of stools in bacillary dysentery is usually greater and the amount of each stool less in quantity. The stool of bacillary dysentery is of a milky whiteness from the large number of pus cells or composed of gelatinous, reddish mucus, while that of amoebic dysentery is tinged with disintegrated blood giving it a grayish-green or brown color. The mucopurulent mass in bacillary dysentery may be flecked or streaked with blood. The therapeutic results following emetine injections are of value in diagnosis. Gangrenous types of dysentery are similar whether due to bacillary or amoebic infection. Chronic dysentery of bacillary origin is much like amoebic dysentery clinically. Manson-Bahr and Gregg recommend the use of the sigmoidoscope in the diagnosis of chronic amoebic ulcerations. In the evening the patient takes ½ ounce of castor oil and the next morning a soap and water enema is given followed by 15 minims of laudanum. The patient is put in the lithotomy position. No anaesthetic is used. The pain in introducing the instrument is greater in chronic bacillary ulceration cases than in amoebic ones. Scrapings can be made for microscopic examinations. Nisbet has reported the diagnosis of a case of balantidial ulceration by use of the sigmoidoscope. =Laboratory Diagnosis.=—The mucoid mass of amoebic dysentery is often brownish. The pathogenic amoeba shows active finger-like processes and in acute attacks often shows contained red cells. In the fresh specimen of the milky mucopurulent mass of bacillary dysentery one observes large numbers of pus cells and particularly very large phagocytic cells which greatly resemble amoebae. Upon staining with Gram’s stain one may find numerous Gram-negative bacilli in the cytoplasm of this cell. These large cells which resemble amoebae are often vacuolated, thus intensifying the similarity. They are nonmotile, however, and do not show the small ring nucleus which is so characteristic of the vegetative human amoebae. The nucleus of the confusing cells is also larger, approximating one-fourth the size of the cell. Bacillary dysentery stools show an absence of Charcot-Leyden crystals which are often present with amoebic stools.