The only remarkable difference between the mucus of colica mucosa and other intestinal mucus is the fact that the former contains fewer cellular elements than the mucus in catarrh of the intestine (N. Jagic, anatomic finding).

This peculiarity seems to indicate that in the case of colica mucosa we are not dealing with an inflammatory product; but otherwise no light is thrown on the mechanism of the attacks. Nevertheless it is apparent that the mucus in the disease we are discussing must possess some peculiar properties. Otherwise this mucus, being a slippery mass, should be evacuated from the intestine shortly after it is secreted with the same facility at least as scybala of fecal matter. At this juncture we are for the present forced to have recourse to hypotheses. It is possible that the secretion of mucus occurs under the stimulus of nervous irritation and that it is from the very beginning constituted differently than normal mucus - i. e., is more sticky in consistency, has a greater tendency to adhere to the portion of the mucosa in which it is produced and consequently accumulates. Analogous conditions are seen in the salivary glands, for it is well known that stimulation of the facial nerve causes the sub-maxillary gland to secrete an abundant quantity of very watery and barely stringy mucus, whereas stimulation of the sympathetic nerve causes the secretion of very thick, tough, gelatinous and very stringy mucus that accumulates at the orifice of the secretory duct in the form of tenacious lumps. As we have every reason to believe that certain nervous influences play a role in the pathogenesis of colica mucosa, the hypothesis may be permitted that the chemical character of the secreted mucus, in particular its tenacity and stickiness, are changed under the influence of abnormal irritation of the intestinal mucosa. No experimental data have been furnished so far to demonstrate this hypothesis. Possibly we do not require an assumption of this character at all. I have already called attention to the fact that colica mucosa is almost without exception accompanied by a severe degree of constipation. The absorption of water from the feces that pass through the lower portions of the large intestines is consequently very considerable, and there can be r.o doubt that the recently secreted masses of mucus that are present in this locality are subjected to the same withdrawal of water as the feces; consequently the mucus becomes dryer and thereby loses its elasticity and motility; its plasticity and its stickiness, on the other hand, increase. As soon as these two properties of the mucus reach a certain degree the adherent masses can only be removed from the intestine by violent contractions of the bowel-wall that are usually accompanied by pain. In this way an attack may be brought about; the direct determining cause being the mass of the mucus itself and possibly, in addition, certain chemical changes in the mucus that are not understood but that lead to the generation of irritating products; a third factor that determines the onset of the attack is probably also certain ner vous influences. Every one must needs recognize that, in addition to the physical and chemical constitution of the mucus, nervous factors must also play a role in starting an attack of colica mucosa, for a study of the history of these cases reveals clearly that the patients are afflicted with some neurotic taint. An analogy is offered by the colicky attacks that occur in other body cavities that are inclosed by a smooth musculature.

As we understand and explain the matter the mechanism of an attack of colica mucosa is therefore quite easily interpreted. The disease, if we are right, can only appear in its typic form - i. e., in the form of periodic passages of mucus with or without pain, if there is a certain degree of sluggishness of the bowels. In this respect I agree altogether with other writers who have chronicled their clinical experience in this field, and in particular with Is. Boas (1. c. pag. 592). If Boas, however, in this portion of his work and also in several other places, declares colica mucosa to be a simple symptom of constipation and altogether dependent on the latter, I cannot agree with him in this respect. While recognizing that periodical expulsion of membranous masses may frequently occur in hysterical and neurasthenic women, Boas proceeds to say: "As we know that in subjects who are predisposed a condition of chronic and obstinate constipation may prepare the soil for the development of a great variety of nervous and hysterical disturbances, we need no longer consider colica mucosa to be a symptom of hysteria or of neurasthenia but essentially a symptom of constipation; for colica mucosa appears as soon as obstinate constipation is once fully established and disappears as soon as the constipation is relieved." That colica mucosa may be successfully treated by removing and curing constipation one of us (Von Noorden, 16) demonstrated to be the case some time ago, and even to-day we maintain this point of view most vigorously. But we have occasion to treat some thirty or forty cases of chronic constipation with a great variety of nervous, hysterical and neurasthenic symptoms before we encounter a case of colica mucosa, even though the peculiar character of our professional work and the class of cases we are apt to encounter would naturally bring a larger number of difficult cases of colica mucosa to our attention than to the attention of the general practitioner. In contradistinction to Is. Boas, and in full agreement with Nothnagel, v. Leube and others, we arrive at the conclusion, therefore, that in addition to general hysteria or neurasthenia certain morbid changes in the secretion of mucus in the intestine play an important and determining role in the genesis of the disease. Neither constipation alone nor neurasthenia alone nor the common combination of these states can produce colica mucosa unless at the same time there is some involvement of the nervous apparatus that governs the secretion of mucus in the large intestine. This characteristic involvement of the nervous apparatus can best, according to Nothnagel, be called a secretory neurosis.

We would only be justified in departing from this view if it could be shown that the constipation produces an inflammation and an inflammatory hypersecretion of mucus; if this could be shown the periodicity of the attacks might possibly be explained on the basis of certain mechanical conditions that would be thus created (rapid absorption of water, comp. above). Against this view, however, numerous arguments can be adduced. In the first place the anatomic findings (see above) in these cases; in the second place, clinical experience and observation all speak against this conception of the disease. If we assume the existence of definite anatomic changes it is hard to comprehend why the patients feel perfectly well in the intervals between the attacks and why in typical cases of colica mucosa the mucus may completely and permanently disappear from the stools within a day if the action of the bowels is regulated and the condition of constipation is temporarily relieved. If, on the other hand, we assume that the disease is due to the existence of some morbid nervous reflex-process, we can readily understand why this must occur, for as soon as the irritation of the dry hard scybala is removed there is no further occasion for morbidly increased reflex activity on the part of the intestinal mucosa.