Dr. Treves says: "The colon being the part of the bowel involved in obstruction due to fecal accumulation, it may be further assumed that the blocking of the gut will most usually concern its lower or terminal parts. Accumulation of feces is most common in the rectum and sigmoid flexure, and then in the cecum. Masses of feces may block the colon at any point, and more particularly at the flexures of the bowel. Still, the three common sites of the accumulation are those just named. The accumulation in the colon may assume the form of a more or less isolated nodule or mass. Thus a considerable lump may be found in the cecum or sigmoid flexure and the rest of the colon be comparatively clear of any gross accumulation. An isolated lump may even persist after free purgation. On the other hand, the accumulation may assume the form of several isolated fecal masses. One of them may occupy the cecum, another the transverse colon, and possibly a third the sigmoid flexure. The bowel between these masses may appear to be fairly clear." A number of the exciting causes of inflammation of the lower or terminal portion of the large intestine have been mentioned. It cannot, however, be too strongly emphasized that chronic inflammation of the colon and rectum results in hyperkinesis (excessive muscular irritability) and contraction of the diseased portion invaded, thereby retarding or preventing the passage of feces and gases. A portion of the daily accumulation of feces in the sigmoid may pass through the diseased rectum every day, but not without increasing the inflammation and the spasmodic contraction; this in time inhibits the elimination of the accumulating feces, which by undue retention become condensed and hardened. Each day will then be a repetition of the abnormal and partial effort of the organ to accomplish the act of defecation, and there will be no thought of the cumulative and chronic intoxication (poisoning) of the system from the imprisoned feces and gases. It may be stated without reservation that the rectal canal cannot be involved in chronic inflammation without involving the anal canal, and _vice versa_. One half of civilized people are suffering from chronic constipation, and very nearly the remainder from semi-constipation. The semi-constipated are now under consideration. The chronic cases are those that have a _complete_ impaction of feces in the terminal portion of the sigmoid and rectum; the semi-constipated have the usual daily _partial_ impaction, that is, an incomplete or partially successful evacuation of the contents of the bowels: the incompleteness is due to disease of the anal and rectal canals.