lesion, disproportionately trifling; or they may be altogether absent, even when the colon is extensively diseased. There is, therefore, endless variety in their character, urgency, and significance. As a general rule, the nearer to the rectum the lesions, the more urgent the tenesmus; the nearer to the cæcum, the more urgent the griping. These two symptoms, together with the presence of points of localized tenderness, form, in many cases, a fair guide to the location and extent of the lesions.
Clinically, the dysenteries are conveniently arranged according to what may be presumed to be the gross characters of the attendant intestinal lesion.
Catarrhal dysentery.— A common history to receive is that for some days the patient had suffered from what was supposed to be an attack of diarrhœa. The stools, at first copious, bilious, and watery— perhaps to the number of four or five in the twenty-four hours— had latterly, and by degrees, become less copious and more frequent, less fæculent and more mucoid, their passage being attended by a certain and increasing amount of straining and griping. On looking at what was passed, the patient had discovered that now there was very little in the pot except mucus tinged, or streaked, or dotted with blood; a tablespoonful, or thereabouts, being passed at a time. By degrees the dysenteric element entirely supplanted the diarrhœa; so that when seen by the physician the desire to go to stool had become almost incessant, the effort to pass something being accompanied by perhaps agonizing griping and tenesmus. The patient has hardly left the stool before he has a call to return to it, and he may be groaning and sweating with pain and effort. The suffering is sometimes very great; nevertheless, with all this suffering there is often very little fever, the thermometer showing a rise of only one or two degrees.
In another type of case the incidence of the dysenteric condition is much more abrupt. Within a few hours of its commencement the disease may be in full swing. The stools, at first fæculent, soon come to consist of little save a yellowish, greenish, or dirty-
