mencing about the tenth or twelfth day of the disease, and by the end of the third week being complete. This is what probably occurs in those cases already alluded to, where the disease is mild and of short duration (see pp. 547 and 587), convalescence commencing about the middle or end of the second week. According to Aitken, the material in the glands is most often got rid of by the vesicles rupturing in the ordinary way,' and discharging their contents into the bowel; but from what has been already stated, it follows that this view is founded on a misconception of the normal structure of the glands. The function of the glands, moreover, is that of absorption, not of secretion or elimination.

b. Second Stage. Ulceration of the diseased Peyer's patches may commence in two ways. The mucous membrane becomes softened, and one or more superficial abrasions appear on the surface of the diseased patch, which extend and unite into one large ulcer, and this ulcer proceeds to various depths through the coats of the bowel and even to complete perforation. This is what happens in the case of the plaques molles. In the case of the plaques dures, the whole of the morbid material in the sub-mucous tissue, as well as the super-imposed mucous membrane, becomes detached in the form of a slough, leaving behind an ulcerated surface. This, according to my observation, is the more common mode. The whole of a diseased patch may slough out at once, or it may slough in successive portions. Occasionally, the sloughing appears to extend at once through the entire coats of the intestine, so as to produce perforation. When death occurs between the twelfth and twenty-first days, the sloughs may be seen loosely attached to the intestinal ulcers, as represented in the annexed figure (Fig. 18). These sloughs have usually a yellowish-brown colour from saturation with bile; occasionally they present a dark, spongy, fungating aspect, from being infiltrated with blood.

It is important to determine at what stage ulceration commences. In fatal cases, this appears to be about the ninth or tenth day, but in this respect there are considerable differences according to the intensity of the morbid process, which is, no doubt, more intense in cases fatal within the first fourteen days of the disease than in those which survive longer. Louis, Chomel, Forget, and Hoffmann each record a case where death occurred on the eighth day, but in none had ulceration commenced, although in Forget's case the agminated glands are

Fig. 18.-Portion of ileum, from a case of enteric fever fatal on the 17th day, showing the partially detached sloughs. The morbid process has advanced further in the agminated than in the solitary glands. The mesenteric glands are much enlarged.

described as on the point of ulcerating.

There are several

cases on record, where ulceration has been found as early as the ninth or tenth day; but it may commence earlier or later. In Case LIX. it had commenced on the seventh day; Louis mentions two cases where it had commenced on the eighth day, and in one of Forget's cases it was found on the ninth day to be very extensive. Cases have been already referred to (p. 567), where the ulceration had advanced to perforation as early as the eighth or ninth day. Stoll relates a case where extensive sloughs were formed in the ileum as early as the seventh day,a and Boudet has published minute particulars of a case, fatal at the end of five and a-half days, in which deep ulcers, with partially detached sloughs, were found in the bowel.e There is reason to believe that in rare cases ulceration may commence as early as the first or second day (see p. 472). On the other hand, of four cases examined by Chomel in which ulceration had not commenced, 2 died on the eighth, I on the eleventh, and I on the twelfth, day. Louis and Hoffmann each record a case where ulceration had not commenced on the twelfth day, and one has occurred in my own practice. (Case LXI.) The ulceration always commences in the glands nearest to the cæcum; these are often found extensively ulcerated, though ulceration may not have commenced in the glands higher up.'

c. Third Stage. The stage of the typhoid ulcer' is that which intervenes between commencement of ulceration and the commencement of cicatrization. It is impossible to fix its limits, as they vary in different patients and in different ulcers of the same bowel. The sloughs may be found detached from the ulcers nearest to the cæcum as early as the fourteenth or fifteenth day, but adherent to the ulcers higher up as late as the third week, or even later. The ulcers may be distinguished from other ulcers of the bowel by the following characters-1. They have their seat in the lower third of the small intestine, and their number and size increase towards the ileo-cæcal valve. 2. They vary in diameter from a line to an inch and a half. Close to the cæcum, a number of ulcers often unite to form a mass of ulceration, several inches in extent. 3. Their form is elliptical, circular, or irregular. They are

LOUIS, 1841, ii. 60; HOFFMANN, 1869, p. 39.
BOUDET, 1846.

Chomel records one case, fatal on the tenth day, in which ulceration commenced in the patches farthest from the cæcum, but such an occurrence is quite exceptional (CHOMEL, 1834. obs. 4).

elliptical, when they correspond to an entire Peyer's patch; circular, when they correspond to a solitary gland; and irregular, when they correspond to a portion of a Peyer's patch, or when several ulcers unite to form one. 4. The elliptical ulcers are always opposite to the attachment of the mesentery. They do not form a zone encircling the gut (as may be observed in the tubercular ulcer), but their long diameter corresponds to its longitudinal axis. An elongated ulcer, however, running transversely may result from the confluence of several ulcers originating in the solitary glands, especially in the large bowel. 5. Their margin is formed by a well-defined fringe of mucous membrane, detached from the sub-mucous tissue, a line or more in width, and of a purple or slaty-grey colour: this is best seen when the bowel is floated in water. After the separation of the sloughs, there is no thickening or induration of the edge, as in the tubercular ulcer. 6. Their base is formed by a layer of sub-mucous tissue, by the muscular coat, or by the peritoneum. There is no deposit of morbid tissue at the base of the ulcer, although sometimes fragments of the yellow sloughs may be seen adhering both to the base and edges (Fig. 18).

d. Fourth Stage. The cicatrization of the typhoid ulcer' takes place in this way:-The surface of the ulcer becomes covered with a delicate shining layer of granulation-tissue, which is dove-tailed, so to speak, between the muscular coat and the detached fringe of mucous membrane. The latter becomes adherent from the circumference towards the centre to the subjacent new tissue, and an epithelial covering is gradually formed over the ulcer. This covering cannot, at first, like ordinary mucous membrane, be moved upon the subjacent coat; but after a time it does become movable, and, according to Rokitansky, it is even coated with villi, but the glandstructure which has sloughed out is of course not regenerated. The resulting cicatrix has the following characters :It is slightly depressed, firmer, less vascular, and smoother than the surrounding mucous membrane. When held up to the light, the bowel appears thinner at the part. The depressed spot seldom exceeds two or three lines, but may amount to half an inch, in diameter. It is never surrounded by any puckering, and it never causes any diminution in the calibre of the gut. According to Chomel, all traces of the ulcers after a short time disappear; but Barrallier mentions cases where the

■ Сномки, 1834, р. 128.

g

BARRALLIER, 1861, p. 105.

cicatrized ulcers were distinct at the end of four or five years, and Rokitansky' remarks that he has discovered cicatrices answering to the above description thirty years after an attack of enteric fever.

The period between the separation of the sloughs and the commencement of cicatrization varies; but, as a rule, the reparative process does not commence until some time during the fourth week of the disease. The time necessary for the cicatrization of each ulcer is probably about a fortnight. In one case, where the primary fever lasted three weeks, but where death occurred from complications about the fortieth day, I found all the ulcers in the ileum cicatrized. Cicatriza

Fig. 19.-Pin-hole perforation in the ileum of a girl aged 10, who died on the 18th day of an attack of enteric fever. The perforation is seen in the centre of the ulcer, on the right-hand side of the cut. tion commences in the ulcers nearest to the cæcum, and proceeds upwards. Consequently, when death occurs in the fourth or fifth week of the fever, the intestine may appear at first sight most diseased one or two feet above the cæcum. As already stated, in cases where death occurs during a relapse, the cicatrices of the first attack may be found co-existing with the fresh deposit and recent ulcers of the relapse (see pp. 554, 576.) But the process of cicatrization is occasionally delayed, sometimes for weeks after the termination of the primary fever. The ulcers become chronic, or, as some pathologists say, atonic.