This occurs in the acute form, but more frequently as a chronic affection; it is commonly presented to the morbid anatomist in the latter shape.

Both generally offer the symptoms common to catarrhal inflammations. Relatively to the chronic form, we have the following observations to make:

It may be developed gradually in consequence of repeated attacks of acute inflammation, or be left as a residuary affection after the incomplete cure of the latter; or, as is very frequently the case, catarrhal inflammation results from an extension of gonorrhoeal catarrh to the bladder. It may also be induced by the continued irritation of long-retained and decomposed urine, as is the case when the discharge of the urine is impeded; or lastly, by the irritation arising from calculi.

It offers various degrees; from a pale circumscribed redness, occasionally surrounding the crypts only, slight opacity and thickening, increase of villosity and secretion of a grayish-white liquid mucus, to a dark reddish-brown, slaty or bluish-black discoloration, accompanied by considerable spongy tumefaction, and the secretion of mucus, which is partly vitreous and clotted, partly yellow and puriform (blennorrhcea). The longer the disease lasts, the more the mucous membrane, from its increased irritability and from the permanently increased innervation of the muscular coat, becomes hypertrophied; the cavity of the bladder is diminished in consequence, and if this condition attains a certain point, paralysis of the muscular fibres and consequent dilatation of the bladder ensue.

In this secondary condition, after the affection has lasted a considerable period, a rapid exacerbation of the chronic catarrh is frequently brought on by the irritation exerted upon the vesical mucous membrane by the accumulation of decomposed alkaline urine. The inflammation speedily attains a high degree, and terminates in exudation, fusion of the mucous tissue, suppuration, and gangrene.

Under these circumstances the bladder is found dilated, and filled with decomposed, intensely alkaline urine, mixed up with blood of a brown color, viscid mucus and pus, sanies, lymph, and detached portions of mucous tissue in the shape of discolored flocculi or larger patches. From this liquid, which offers a pungent ammoniacal odor, a soft, pulverulent, mealy sediment, consisting of calculous matter bound together by lymphatic exudation, is deposited upon the internal surface of the bladder. The parts themselves are discolored, and present a dark reddish-brown, greenish-gray, or bluish-black hue. The mucous membrane, when presenting a dark-red color, appears spongy, softened, and pultaceous, is easily detached and bleeds; when chocolate-colored or greenish it is found purulent, infiltrated with sanious matter, or converted into a friable flocculent tissue, which is traversed by the urinary sediment; or if the process of solution is completed, and the mucous membrane has become detached, the surface of the cellular and muscular coats is exposed in larger or smaller sinuous patches, appears frayed and pulpy, infiltrated with purulent sanies, discolored, softened, and friable. Finally, the muscular coat is involved in the suppurative and gangrenous destruction, and general peritonitis ensues; or even before this takes place sinuses are formed between the vesical membranes, the parietes of the bladder are eaten through, and present a cribriform appearance, and the urine exudes into the surrounding cellular tissue and into the peritoneal cavity. The bladder is converted into a paralyzed sac, the coats of which are thickened, though they yield on slight pressure, they are discolored, and infiltrated with pus and sanies.

The disease commonly proves fatal, either directly or by extension of inflammation to the ureters and kidneys.

In other cases the disease has slight exacerbations from time to time, being limited to a more or less circumscribed spot, which undergoes a slower process of suppuration, and at last becomes perforated. If, under such circumstances, the tissues external to the bladder have become the seat of inflammatory action previous to the occurrence of perforation, a diffuse extravasation of urine is prevented in one direction by inflammatory condensation of cellular tissue - in another, by free peritoneal exudation and agglutination to an adjoining organ. The circumscribed suppuration progresses slowly, and induces fistulous destruction of the tissues, and communications between the bladder and the external surface of the body, or with other hollow organs.

Catarrh of the bladder is of importance, under all circumstances, from its extension to the ureters; and, in bad cases, from its complication with renal inflammation. It may also extend to the seminal ducts.

A very important variety of vesical inflammation is that developed in the course of paraplegia; it generally passes into gangrene, and terminates fatally. The mucous membrane becomes the seat of extensive congestion and suffusion, which spread to the submucous cellular tissue and the muscular layer; the bladder assumes a dark-red hue, is friable, dilated, and filled with urine; or it is empty and collapsed, and the mucous membrane is then partly invested with a coat of ill-looking lymph, partly infiltrated with pus, partly fused into a pulpy sanious tissue. The muscular fasciculi are pallid, ash-colored, and friable, and the cellular tissue is infiltrated with pus and sanies. The cavity of the bladder contains a sanguineous, dirty brown, or chocolate-colored urine, of a pungent ammo-niacal odor; this is mixed up with the various products of the process, and deposits a white, soft, pulverulent sediment.

This affection presents an extremely asthenic character, and although we are ready to admit that in many cases it originates, together with the concurrent inflammation of the kidneys, in paralysis, we consider that in others the irritation produced by the alkaline urine stagnating in the bladder, is to be viewed as the chief or as a collateral cause.