the scales acquire a blackish color, the designation psoriasis 'nigra or nigricans is employed.

Psoriasis frequently develops without any other morbid disturbances. In other instances slight febrile movement and pallor

occur. At times pain and swelling, and subsequently deformity, also appear in some joints. Some patients complain only of the disfigurement. Others are distressed by the itching, burning, and

pain. In cases of diffuse psoriasis the movements of the joints are not rarely interfered with, and painful fissures may readily form. Psoriasis generally pursues a chronic course, and, untreated, persists for several years. Although it is curable, recurrence takes place as a rule. Nephritis and albuminuria may appear after longcontinued psoriasis.

Serious diagnostic difficulty arises but seldom. In cases of syphilitic psoriasis the scales are less abundant, the plaques appear especially upon the palms of the hands and the soles of the feet, and other syphilitic lesions are present besides. In contradistinction from eczema, weeping and marked itching of the skin are wanting with psoriasis. Pityriasis rubra is characterized by its unfavorable course and the complicating marasmus. Lichen ruber is attended with the presence of small efflorescences, generally as large as the head of a pin, arranged in groups side by side, and followed by slight desquamation.

Anatomic Alterations.-Psoriasis is attended with elongation and expansion of the papilla of the cutis, and dilatation of the blood-vessels, which are surrounded by accumulations of round cells. The lowermost layer of the cells of the mucous lamina of the epidermis, arranged in the form of palisades, is in a state of proliferation, while the remaining cells have lost their thorn-like processes.

Etiology.-Psoriasis is frequently an hereditary disease, although the disorder but rarely appears as early as childhood. A toxic variety of psoriasis is also believed to exist, resulting from the employment of borax. Isolated observations of inoculation are on record, although nothing is as yet known with regard to a germ of psoriasis. In many cases it is impossible to elicit a cause for the disorder, which has been attributed to unsuitable food, excessive indulgence in alcohol, and the like.

Prognosis. Psoriasis is, as a rule, unattended with danger to life, although it is often an obstinate disorder, concerning which one can never know whether it will remain permanently cured.

Treatment. In the treatment of psoriasis, internal and external remedies should be combined. Among internal remedies, arsenic is deserving of the warmest commendation :

༣.

each, 5.0 (75 minims).-M.

R Bitter-almond water,
Solution of potassium arsenite,
Dose: 10 drops thrice daily after eating.

In addition, the patient should take a sulphur-bath daily, and subsequently remove the scales upon the skin by means of a stiff brush that has been dipped in a soap of sulphur and tar. The sulphur-bath should have a temperature of 35° C. (28° R.-95° F.), and contain 150 grams of potassium sulphid. The patient should remain in such a bath for from half an hour to an hour, but he must be watched by an attendant, in order that he may

not, unobserved, be overcome by the vapors of hydrogen sulphid and be drowned. The following formula may be employed as a sulphur-tar soap:

Green soap,
Liquid pitch,

Precipitated sulphur,

Dilute alcohol,

Apply externally.

each, 25.0 (ounce).-M.

Should pain and excessive redness result from active irritation of the skin, the tar-soap should be omitted for a few days and be replaced by inunctions of borated ointment :

R Boric acid,
Wool-fat,
Lard,

For external application.

3.0 (45 grains);

each, 25.0 (ounce).-M.

For the treatment of so annoying and so frequent a disorder as psoriasis a large number of remedies have naturally been recommended, of which a few may yet be mentioned. Internally, large doses of potassium iodid, thyroid extract, and salicylic acid have been recommended, although I have observed no good results from any of these drugs. Of external remedies, pyrogallic acid and chrysarobin especially may be mentioned, both employed in the form of ointments containing from 5.0 to 10.0 (75 to 150 grains) to 50.0 (11⁄2 ounces). Courses of treatment at sulphurous or indifferent baths have been much prescribed.

PITYRIASIS RUBRA.

Pityriasis rubra is an uncommon disease of the skin, concerning whose etiology nothing is known. The disorder occurs most frequently in men. The affected skin becomes reddened, and undergoes desquamation. The latter is generally branny, and occurs but rarely in the form of large scales. At times the skin becomes thin and, to a certain degree, unduly tense, so that ectropion of the eyelids develops, and the movements of the hands and the fingers are interfered with, the latter assuming a persistent semiflexed position. The skin exhibits a tendency to fissures; at times the hair falls out. The disease either involves the entire body simultaneously, or arises from several points upon the skin, and gradually extends over the entire body. The patients at the same time gradually fail in strength, are not rarely attacked by tuberculosis of the lungs or tuberculosis of the lymphatic glands, and death frequently results from marasmus. In the diseased areas of skin dilatation of the vessels of the cutis, accumulation of round-cells, and flattening and atrophy of the papille have been found. The epidermis, and the sebaceous and sudoriferous glands also have been atrophied. Occasionally, many pigmentcells have been present in the cutis.

The treatment consists in tepid baths and oily inunctions, while internally potassium iodid may be employed.

PAPULAR INFLAMMATIONS OF THE SKIN (PAPULAR DERMATITIDES).

PRURIGO.

Symptoms, Diagnosis, and Prognosis.-Prurigo is attended with the formation of nodules (papules) upon the skin, which are associated with excessive itching (pruritus). As a rule, the disorder begins in earliest childhood, most frequently toward the close of the first year of life, and appears earliest on the legs, subsequently extending to the thighs, the forearms, the upper arms, and even the trunk and the face. Papules are generally wanting upon the scalp, but here active formation of scales takes place. The flexor aspects of the joints always escape. In the incipiency of the disease repeated attacks of urticaria occur. Then small nodules appear beneath the epidermis, which at first can be better felt by passing the fingers over the skin than they can be appreciated with the eye. Gradually these papules project distinctly above the surface of the epidermis, and the skin often feels rough like a grater. The papules are in part pale, and in part red, and when punctured and compressed discharge a clear fluid. They are often covered by epidermic scales. The patient is, at the same time, harassed by intolerable itching, which is especially aggravated by heat, and therefore becomes particularly distressing at night in bed, preventing sleep, and resulting in emaciation and exhaustion. Some clinicians contend that the itching precedes the formation of the papules. The persistent and vigorous scratching leads to the formation of crusts, and even of pustules upon the skin. After the disease has existed for some time the skin acquires a brownish discoloration (melasma), in consequence of free bleeding from the scratching, and a chronic inflammatory, infiltrated, and thickened character. Frequently adjacent lymphatic glands become enlarged-prurigo buboes; the inguinal lymphatic glands especially not rarely appear as enormous packets beneath the skin. The patients slowly undergo progressive emaciation. Occasionally albuminuria develops. The disease generally pursues a chronic course, and not rarely persists throughout life. Recovery can be expected only if the disorder has not existed for more than four years. Often numerous remissions and exacerbations occur, and improvement is especially prone to take place during the

summer.

Anatomic Alterations.-Little of a definite nature is known with regard to the anatomic alterations of prurigo. Circumscribed swelling and enlargement of the papillary bodies of the cutis, together with cellular proliferation, and also multiplication of the cells in the Malpighian layer, have been described.

Etiology.-Prurigo is not rarely an hereditary disease. In addition, unsuitable food, rachitis, scrofulosis, pulmonary tuberculosis, and pseudoleukemia have been mentioned as causative factors.

Treatment.-Inunctions of the skin with green soap should be made at night, and a sulphur-bath (100.0 potassium sulphid to a full bath at 35° C.—95° F.—of two hours' duration) should be taken in the morning. After the bath the skin should be anointed with carbolated ointment (5:50).

In addition, subcutaneous injections of pilocarpin and the treatment applicable to psoriasis have been recommended.

LICHEN OF THE SCROFULOUS.

Symptoms and Diagnosis.-Lichen of the scrofulous is attended with the presence of papules about the size of a pin's head, from pale red to brownish-red in color, with a small thin crust at the center. If the latter be removed, a hair will be found at the center of the papule, and whose follicle exhibits a clearly defined, slightly elevated boundary. The papules are unassociated with other symptoms. The first papules generally appear upon the back, particularly in the scapular region, upon the chest, and in the hypogastrium. Subsequently the extremities, the trunk, and the head also are involved. Upon the arms the flexor surfaces especially are affected. It is distinctive for the papules to be arranged in groups or in circles. The disorder occasionally persists for years.

Anatomic Alterations.-Microscopic examination of the skin discloses round-cell accumulations in the vicinity of the hairfollicles, plugging of the latter with round cells, and obstruction of the excretory ducts with accumulated epidermic cells.

Etiology. The disease generally occurs in scrofulous children, less commonly in those with pulmonary tuberculosis, and but rarely after the twentieth year of life. The patients generally present a pale and fatty skin.

Prognosis. The disorder is unattended with danger, and is

curable.

Treatment.-The skin should be anointed several times daily with codliver-oil and also internally 25 c.c. of the same oil should be administered daily.

LICHEN RUBER.

Symptoms, Diagnosis, and Prognosis.-Lichen ruber is attended with the formation upon the skin of red papules averaging in size that of a pin's head, which are at times acuminated and covered with a thin scale of skin-acuminated lichen ruber; and at other times are rather flat, with a depression at the center