In =dogs= there are violent and painful efforts to defecate, which may be fruitless, or may lead to the expulsion of small masses of dry, earthy looking fæces, smoothly moulded on the surface, coated with mucus, streaked it may be with blood and highly offensive in odor. The anus may be puffy and swollen with mucopurulent secretion from the anal glands, which soils the hair of the hips and tail. If the abdomen is flaccid, manipulation with both hands on opposite sides usually detects a solid mass representing the impacted rectum and colon, and extending from the pelvis forward, often to the sternum. The same mass will be reached by the oiled finger introduced into the rectum. Both methods of exploration are painful and may call forth cries from the patient. The abdomen is usually distended, largely from the impacted fæces, in which case it gives a flat sound on percussion, or from gaseous emanation, in which case it is tense, resilient and resonant. Colicy pains are liable to appear, and vomiting at first of food only, then more or less yellow and bilious, and finally of distinctly feculent matters. For a time appetite may be retained, but this is gradually lost. There may supervene diarrhœa, which in favorable cases may lead to expulsion of the impacted mass, but in others it fails to completely dislodge it. The patient is dull and spiritless, inclined to lie curled up in dark corners, and when raised walks slowly and stiffly, with the tail carried straight or slightly to one side. The male urinates like a bitch without lifting the leg. The nose is dry, the tongue furred, the teeth usually covered with tartar, and the breath fœtid. There is at first no hyperthermia, but some rise of temperature attends on the advance of the disease, and the auto-poisoning by absorbed products of the putrefaction of retained fæces. The disease may last a few days only or it may continue for weeks or months. In the last case intestinal catarrh, ulceration, and circumscribed necrosis are likely to supervene and the animal may die of auto intoxication, acute peritonitis or enteritis. Yet the majority of cases in the dog reach a favorable termination, or recover with remaining cicatrices, strictures or dilatations.