The catarrh may be more or less confined to the colon, or attention may be drawn to the colon because the evidences are more pronounced than in catarrh of the duodenum, jejunum, or ileum. These cases, again, may be divided into two groups - (a) Those in which there is a definite local lesion: (1) Ulcerative colitis, (2) tubercular and syphilitic ulcers, (3) malignant disease; (b) Those in which no definite pathological cause can be found: (1) Mucous colic, (2) mucous colitis, and (3) mucomembranous colitis.

If the affection be due to stricture of the bowels from syphilitic or malignant disease, there will be constipation in the first instance; this is succeeded by diarrhea and other symptoms of the causative disease. In tubercular ulceration there is nearly always diarrhea from the first. Belonging to this group is the morning diarrhea which affects various people. It is usually found that the trouble is due to the presence of an ulcer in the colon, probably in the sigmoid flexure.

Ulcerative colitis is a different matter. It is common in asylums, where it is known as asylum dysentery, and it also occurs among people outside such institutions. The first symptom is abdominal pain, followed by diarrhcea; the act of defalcation is attended by pain, but there is not such a frequent desire to defalcate as in dysentery. The motions are foul, liquid, and dark coloured. They contain blood; but this is not always fresh, it is partly combined with the faeces, partly in clots looking like red-currant jelly. In addition, the faeces may contain pellets of mucus and shreds of mucous membrane. The patient becomes seriously ill, weak, exhausted, and the temperature may rise to 100° or 1030 F. The condition is a dangerous one, and about 50 per cent of cases in asylums die in a month or two after the onset of the disease from severe diarrhcea or profuse haemorrhage.

Mucous colic, mucous colitis, or membranous colitis is always attended by obstinate constipation. The faeces are accompanied by mucus; this may be clear pellucid mucus, like raw white of egg, in pellets or masses sufficient to cover the faeces; the mucus may be in flakes like pieces of boiled white of egg; or it may consist of a membranous cast of the bowels, which is evacuated entire or broken into shreds.

The causes of this condition are unknown or unsettled. In the majority of cases no pathological change of the coats of the bowels can be found, in other cases there is some thickening of the structures due to chronic hyperaemia. The only symptom referable to the bowels is the obstinate constipation, although there may be pain or aching along the course of the colon and tenderness on pressure; and in "mucous colic" violent attacks of pain, due to spasm in the colon, precede the discharge of a large amount of mucus. The prolonged constipation, often lasting for years before the occurrence of mucous or membranous colitis, is said to be the cause of an excessive formation of mucus. We can easily understand that the retention of faeces is a source of irritation to the mucous glands in the coats of the bowels. These crypts, lined with mucous cells, ordinarily provide sufficient mucus to lubricate the passage and keep it moist - no more! The secretion is a glairy, transparent, viscid fluid, such as may be seen covering scybala and hard motions in an ordinary case of constipation. Constipation causes, first, an excess of ordinary healthy mucus; secondly, it provokes some change in the mucous cells so that the secretion is altered in character from a glairy, transparent fluid to something like a paste, which forms a mucinoid coating to the bowels. But however changed the discharge may be, it is always mucus or mucinoid in character, and never contains fibrin such as would occur from inflammatory exudations. This paste-like substance may be protective in character, but it does not lubricate the bowels or assist in defalcation. The nervous system is always seriously disturbed in this disease, owing to the toxaemia arising from the constipation and intestinal indigestion; so much are the nerves deteriorated that some authorities consider the pathological condition a secretion neurosis. Moreover, the longer the disease lasts the more neurotic becomes the sufferer.

The patients are always chronic dyspeptics, usually eating little, suffering pain after food; they are thin, pale, anaemic. Their mental condition is that of the pessimist; they view everything from the worst side, become gloomy, despondent, and melancholic. They are not always passing "skins" or large quantities of mucus. When their motions are practically free from this material their health is improving; when their health is worse, the despondency more marked, the feebleness pronounced, and the general condition is deteriorating, they are about to pass "skins," or large quantities of mucus; and when they have got rid of them their health is again improved.

Mucous and membranous colitis are sometimes due to the lodgment of a foreign body in the colon. Thus a patient who had suffered from dyspepsia for more than a year, who ate little and suffered from constipation and mucous colitis, was soon cured after the removal of extraneous substances. She was given a diet of bland and unirritating food, such as for intestinal catarrh in general. The constipation was treated daily by large enemata of warm water transformed into an imitation of Plombieres water by the addition of alkalies. This treatment brought about an improvement in the general condition. One day she spontaneously passed some jet beads, the size of a pea, which had been swallowed more than a year previously; some more beads were passed a few days later; and from this time forwards the recovery progressed rapidly, and within a short time the patient was apparently completely cured.