of ammonia dissolved in distilled water, in the dose of the one-twentyfourth of a grain, have been recommended as peculiarly efficacious.

In some cases of uncommon severity, or where the disease has been improperly treated in its early stages, a rupture of the vesicles takes place, followed by ragged ulcers, which spread, often with great rapidity (H. exedens). These ulcers should be treated by carrot poultices, or touched with a weak solution of nitrate of silver, or chloride of soda.

11.-Psoriasis.

Scaly Tetter-Dry Scall-Lepra Alphoides.

This form of squamous eruption consists in a rough and scaly condition of the cuticle, sometimes in separate patches, varying in size, and of irregular form, and sometimes occupying continuously a large portion of the surface. For the most part, psoriasis is accompanied with rhagades or fissures of the skin.

Soon after the appearance of reddish points or projections on the skin, small white or pearl-like scales appear, either separate or in clusters, or surrounding a central pink-colored space, with a slight discoloration of the surrounding skin. In other cases, the patches are of a reddish or brownish color, interspersed with fissures, and accompanied with intense itching, or a sense of burning, increased by heat or friction. Sometimes ulceration occurs, with the discharge of a purulent fluid, which latter, intermixed with the scales, on becoming concrete, forms a more elevated crust. The scales are usually surrounded by a circle of deep rose color, which is increased in intensity by exertion, or by food of a stimulating quality: Beneath the scales, the skin is red and irritable. When the patient is in bed, the scales often become detached in great quantities, and, by their friction, aggravate the tingling and itching.

When the disease occurs in the neighborhood of joints, or parts endowed with considerable motion, blood frequently issues from the fissures, accompanied by severe pain and smarting.

Psoriasis is, occasionally, at its commencement, formed of small distinct patches, with irregular circumferences (P. guttata). These appear on almost every part of the body, even on the face. In other cases, the patches are of some extent, and also irregularly circumscribed (P. diffusa). The patches, again, may present a tortuous or serpentine appearance (P. gyrata). In some instances, the patches which were at first separate and irregular, become, in a short time, confluent, until at length the greater part of the surface of the body is covered with a universal scaliness, interspersed with deep furrows, and attended with a harsh, stiff, and thickened state of the epidermis (P. inveterata).

In infants, the disease appears commonly upon the cheeks, chin, forehead, nates, abdomen, &c. When the face is affected, the eyes sometimes partake of the inflammation; generally the mucous membrane of the nose becomes inflamed and thickened, causing snuffling, difficulty of respiration, and some discharge from the nostrils.

In protracted cases, there is often great emaciation, which rapidly

increases until death takes place. The disease, in early life, is commonly attended with more or less affection of the alimentary canal, which may have been the primary cause of the eruption, and may impede its cure.

Psoriasis generally occurs among the children of the poor, who inhabit unhealthy localities, and is mainly to be attributed to bad food and bad nursing, in conjunction with the morbific influence of an impure and confined atmosphere, the want of proper exercise, and a neglect of personal and domestic cleanliness.

Its treatment consists in a change to a more wholesome atmosphere, an improved diet, proper clothing, and frequent tepid bathing, with a course of medication adapted to restore to their healthful condition the functions of the digestive organs. Frequent ablutions of the more irritable parts with warm water or mucilaginous fluids, will, in general, aid materially in accomplishing a cure. If there be much irritation, with constant fretfulness, and want of sleep, the parts may be bathed with the watery solution of opium. This may also, with an addition of carbonate of soda, be administered internally, should there be nothing to forbid its use. When severe local inflammation exists, leeches around the edges of the squamous patches will be proper.

On the subsidence of the local irritation, the sulphur-bath may be employed, and repeated every two or three days, provided it is not found to increase the irritation of the skin. If the latter effect result, the bath should be at once suspended, and gentle purgatives administered, at such intervals as will be sufficient to preserve the bowels freely open. The following has been recommended, as one well adapted to these cases:

R.-Sulph. præcip. 3j.
Magnes. cale. 3ss.

Rhæi, gr. xxiv.

Bi-tart. potassæ, gr. xxiv.-M. f. ch. No. xij.

In the chronic stage of psorias, the decoction of dulcamara, and small doses, three times a day, of the solution of the arsenite of potassa, will be proper. In cases attended with considerable derangement of the alimentary canal, with unhealthy discharges from the bowels, in which, of course, the arsenical solution would be improper, the decoction of dulcamara may be employed, in conjunction with the spirits of turpentine: three to eight drops or more of the latter, according to the age of the patient, may be given three times a day, dropped on a piece of mint candy.

When the scales do not readily separate, they may be carefully touched with the liquor potassæ, or dilute hydrochloric acid; or the ointment of the nitrate of mercury may be used, taking care to wash off that already applied before reanointing with it.

If there ensues a state of considerable prostration, especially if the skin, at the seat of the eruption, acquires a dark or violet hue, the sulphate of quinia should be administered, or some one of the preparations of iron, or the tincture of iodine may be given in doses of from two to eight drops, twice or thrice in the course of the day. A

pure, fresh atmosphere, and the daily use of the warm bath, are, in these cases, all-important.

When psoriasis occurs simply as a concomitant of other diseases, our whole attention should be directed to the removal of the latter; the disappearance of which will very generally be followed by that of the cutaneous affection. This is a rule which will apply generally to all of the diseases of the skin.

12. Follicular Warts.

These consist in hard, white, and rather shining elevations of the skin, usually occurring on the cheeks and forehead. They are often stationary for some time. In some instances, however, one or more of them become enlarged, of a pale pink color, and surrounded by an inflamed margin.

They ordinarily result from an obstruction of the cuticular follicles, causing the sebaceous matter secreted by them to accumulate within their canals, and there concreting, to distend them, and, ultimately, excite an inflammation that often involves for a short distance the neighboring skin. Soon after the inflammation occurs, a suppurative process commences in the follicle, and the sebaceous matter is dislodged; and all disease speedily disappears; but, occasionally, the follicle becomes filled with pus, and an abscess of considerable size results. From a small opening in this an exudation of cheesy matter, mixed with pus, continues for some time to take place, or it may concrete upon the surface and form a crust.

The follicular wart generally occurs towards the close of childhood in both sexes, but more commonly in boys. It is ordinarily produced by derangement of the digestive organs. In females, it is frequently connected with that condition of the digestive and assimilating functions which give rise, at a later period, to chlorosis.

A proper regulation of the diet, brisk but gentle purgatives, pure air, and the warm or tepid bath, followed by brisk friction of the surface, are the only remedies required. In cases in which the derangement of the bowels is of a more serious and extensive character, the proper treatment adapted to the particular character of the intestinal disease present in each case will be demanded.

When the tumors are large, few in number, and of an indolent character, they may be seized with a pair of forceps, and excised by a sharp scissors; or the inspissated matter by which they are filled may be expelled by gentle pressure. When inflammation takes place, suppuration should be promoted by warm fomentations, or a small poultice; and as soon as matter is formed, it should be allowed early to escape by a slight incision.

In some cases, towards the period of puberty, these tumors become the seat of chronic inflammation, and the face then becomes studded with hard, dull, red, and painful pimples (A. indurata), which continue for a long time. They are generally connected with very considerable derangement of the digestive organs. Until the latter are restored to a healthy condition, they very seldom disappear. Various local applications have been recommended for these pimples, but we

must confess we have, in no instance, seen any advantage derived from their use. A course of treatment adapted to the condition of the alimentary canal, with an appropriate diet and regimen, is the only means which, in our hands has succeeded in freeing the patient from the deformity consequent upon acne indurata.

13. Porrigo.

Tinea Favosa-Favus-Tinea Capitis-Scabies Capitis Favosa-Teigne Faveuse-Honeycomb Scall-Scald Head.

Porrigo is one of the most obstinate, disgusting, and infectious, of the simple cutaneous affections of childhood. There are several varieties of the disease. In one (P. lupinosa), an eruption of minute, flat, umbilicated vesicles of a yellow color, occurs upon the scalp, attended by more or less itching. The contents of these pustules, by speedily desiccating, form a number of small circular scabs, of a yellow or fawn color. Each scab is hollowed in its centre, and raised at its edges, and has its base deeply imbedded in the skin, and strongly adherent to it. The scabs gradually increase in size, but still preserve their circular and cupped form.

When the pustules of porrigo occur in clusters on different parts of the scalp, after scabs are formed, their edges approach each other, and by their aggregation give rise to crusts of considerable extent. In these, however, the cup-like form of the individual scabs is readily detected, giving to them some resemblance to honeycomb. Sometimes the cutis is deeply involved, and fissures of considerable extent are formed, from which an ichorous or purulent matter is discharged. Occasionally, according to Alibert, in severe and protracted cases, the cutis, and sub-cuticular cellular membrane are destroyed, and the bone of the skull laid bare. Between the different clusters of scabs the scalp is covered with furfuraceous scales. In some individuals the disease extends to the forehead, temples, and neck; it may occur also upon other and remote parts of the body.

The attendant itching is, in some cases, almost intolerable. causing the patient to scratch himself incessantly and severely. Pediculi, which multiply in great numbers under the edges of, and between the scabs, add farther to the irritation. The smell emitted by the scalp is peculiar and disgusting, resembling that of the urine of the male cat.

When the crusts are removed by the application of emollient poultices, the epidermis is found to be destroyed, and the reticular structure beneath red and inflamed. A yellow, viscous, and fetid discharge exudes from numerous ulcerations; and a number of small abscesses are seen dispersed over different parts of the scalp, of a lenticular form, and appearing as so many centres of inflammation. When the disease is neglected and allowed to proceed, there takes place an almost universal falling out of the hair, leaving the skin smooth and shining. The few hairs that remain are thin, languid, and altered both in color and structure. When the scabs in this form of porrigo are allowed to become perfectly dry, they assume a white appearance, wear off,

break, and detach themselves from the scalp, their remains presenting no regular form.

There is another, and very common form of the disease (P. furfurans), in which there occurs, at first, a slight desquamation of the cuticle of the scalp, often attended with considerable itching. From the affected surface there oozes an ichorous matter, which dries, and forms a scurfy covering to the scalp: The disease gradually and slowly spreads over the greater part of the scalp; while the layers of scurf thicken, resembling a coating of bran, or coarse flour, the lower surface of which is saturated with fluid. Upon freeing the scalp from this adhesive substance, it is found to be divested of its cuticle, presenting a smooth shining surface, like varnish, and usually of a pink color. The hair, in this form of porrigo, becomes matted and glued together; and, when the finger is pressed upon it, the whole mass has, in nearly every part, a soft yielding feel.

The disease is chiefly confined to the scalp, but sometimes extends to a slight distance upon the forehead, in the form of crusts, resembling a portion of bran, cemented by some adhesive fluid, the edges of which are sometimes dry, and perfectly white. Much itching attends the disease, and great numbers of pediculi range freely over the affected parts. Ulcerations to a small extent occur here and there, from which a fluid is discharged. The scalp emits the smell of sour milk. The disease presents itself in other cases, in the form of numerous small, deeply-seated, yellow pustules, of a circular form, and umbilicated, seated upon a circular red patch, which precedes them. The pustules are crowded together, especially around the circumference of the patches. They are commonly each traversed by a hair, and are attended by intense itching (P. scutulata.) Their contents soon concrete, forming a small cupped scab, which adheres by its edges to the adjoining scabs, producing thus a continuous crust, of the form and dimensions of the patch upon which the pustules arose. The individual scabs, in coalescing, lose their cupped form. Around the circumference of the patches, new crops of pustules successively arise, and forming scabs, cover the greater portion of the scalp with a continuous, thick incrustation, of a whitish color, surrounding which, portions of the original blotches, in the form of semi-circles, or segments of circles, are perceived. In these cases no hair is present, excepting around the incrustation, where it forms a sort of crown (P. decalvans). Portions of the scalp are frequently covered with circular patches, varying in size, showing the disease in a more or less advanced stage, with here and there a white and shining space, entirely bald-the intervening portions of skin being covered, to a greater or less extent, with a furfuraceous desquamation. This form of porrigo may extend to the forehead and neck.

In other cases, the disease is more circumscribed. The pustules, on drying, form small brownish, or dark-gray crusts, varying in form and size, and strongly resembling fragments of old mortar, or the plaster from walls discolored by damp and dust; they are often very hard, even of a stony consistence (P. granulata). The patches of disease are generally separated from each other, and are not so deeply imbedded