and arms, and may gradually extend to the lower part of the body. There is at first no change in color, but the skin is hard, rigid, inelastic, and cannot be pinched up into folds. As it goes on, the movements of the limbs are hindered, the joints are more or less fixed, the chest is limited in its respiratory movements, and if the face is affected it loses its power of expression; the mouth can be opened with difficulty, but the eyelids often retain their mobility. Subsequently, the skin becomes shining and glossy, irregular patches of pigment appear, and here and there are areas of vascular dilatation giving a pink or violet color. The secretions of sweat and sebum are diminished. The course of the disease is slow, and it extends over years, eventually, in many cases, subsiding entirely. During this time, the patient's health is practically unaffected, but rheumatism and cardiac troubles have been noted as occasional complications. In the skin itself eczema, erythema, and ulceration may occur.

In some cases, the disease begins with more thickening or cedema of the skin, and this, according to Dr. Crocker, tends to result in an atrophied, rigid, tight condition, which is much less liable to spontaneous recovery than the simply indurated forms.

The disease occurs in young adults and middle-aged persons, less frequently in children, and hitherto not under thirteen months. (See Sclerema Neonatorum.) It is more frequent in women than in men, but little is known of its causes.

In circumscribed scleroderma, or morphea, there is an unsymmetrical patch of two, three, or more inches in diameter, frequently corresponding to the distribution of a nerve. For instance, a patch may occur over the distribution of the supraorbital nerve on the forehead; the trunk near the breast, and the limbs are also common places for the eruption. The patches are irregular in shape, or may be in the form of bands, round or along a limb. They are of a dead-white ivory color, surrounded by a violet or pink zone of dilated vessels. The skin is smooth and dry, and may often be pinched up; it may be level with the healthy skin, or below or above it. The disease lasts several years, and then subsides and disappears, or it may extend into the diffused form, or persist in an atrophic condition. Circumscribed scleroderma is also more common in women than men, and can sometimes be referred to local irritation as a cause.

Anatomy. The epidermis is unaffected except for some pigment in the rete; there is a considerable overgrowth of connective tissue in the corium and subcutaneous tissues; the deeper vessels are surrounded by numerous leucocytes; and the superficial vessels are often contracted and empty. Leucocytes also surround and may obstruct the sweat-gland ducts, and the muscular fibres of the skin are hypertrophied.

Treatment. This is not very satisfactory. The patient should be kept warm at all times, and tonic remedies should be given. Locally, emollient

applications and friction, and shampooing to restore the circulation in the skin, may be tried. Galvanism has also been used.

SCLEREMA NEONATORUM.

This is a peculiar induration of the skin, which is either congenital or begins shortly after birth in feeble infants with deficient circulation. It may begin in the lower extremities and spread to the rest of the body, or it occurs in scattered patches on the thighs, buttocks, trunk, arms, and cheeks. The affected parts feel quite hard and firm, suggesting that the subcutaneous tissue has been frozen. The patches have a well-defined edge, are slightly raised above the surface, and sometimes have a bluish-red color. They only pit after very prolonged pressure. The children are cold and drowsy, with small pulse, and feeble respiration. They often die from collapse or diarrhoea, but occasionally recover. The cause of the change is not well understood. It may be confounded with a true ædema, which pits readily on pressure (Crocker).

Treatment. The child should be kept warm and efficiently fed, by a nasal tube, if necessary.

ELEPHANTIASIS.

This name has, at different times, been used for several diseases, and especially for two distinguished as elephantiasis Græcorum and elephantiasis Arabum. The former is true leprosy, and will be described presently; the latter is now, by common consent, alone termed elephantiasis. It consists of an enormous hypertrophy of the skin and subcutaneous tissues of some part of the body, due to obstruction of the lymphatic channels. It is most common in tropical countries-in the West Indies, Cape Colony, Egypt, South America, China, and Japan, but it occurs sporadically and less frequently in other parts of the world. The legs and the scrotum are the parts most commonly affected. It is not necessarily symmetrical: it may affect one leg alone (Barbadoes leg), or the leg below the knee only, or the scrotum, or the ears, or lips, or an arm, or the lower part of the abdominal wall. If the leg is affected, it becomes enlarged to two or three times its natural size. The skin looks oedematous, but it does not pit on pressure; it is obviously greatly thickened. Where folds naturally occur, as about the knee or ankle, there are deep sulci, and these may be moist from retained sweat or sebum. Pigment is increased in the limb, the surface becomes rough and scaly, here and there are patches of hypertrophied papillæ, and, in other parts, vesicular or moniliform prominences due to dilated and varicose lymphatic vessels. Sometimes these burst, and discharge a more or less turbid lymph. The scrotum has sometimes grown to a tumor weighing more than one hundred pounds.

In tropical countries the disease often begins by attacks of swelling and redness like erysipelas, accompanied by fever, after the subsidence of which the leg is left bigger than normal. A fresh attack of fever and local inflammation after some months again leaves the leg worse than it was after the first, and the evil goes on increasing. Sometimes however, the enlargement is gradual, and not at any time associated with febrile attacks. In England erysipelas and phlegmasia alba dolens are occasionally causes of a permanent elephantic change. Local pressure on veins and lymphatics may cause it, and I have seen it as a part of extreme obesity.

In all cases it would seem that it arises from obstruction to the lymphatics, and though in some cases the method of obstruction can be recognized, this is not so in all. It is only within the last few years that it has been discovered that in the endemic cases of tropical climates the obstruction is due to the presence of the Filaria sanguinis hominis lying within the lymphatic vessels (see p. 725).

Anatomy. The change affects chiefly the subcutaneous layer, which is enormously thickened by the growth of new connective tissue, partly gelatinous, but mostly in dense fibrous bands. The blood-vessels and lymphatics are much enlarged, and sometimes the nerves. The corium and epidermis are only slightly affected.

Treatment.-Very little can be done, except surgically; thus a large scrotum can be removed. But in any other part of the body such a measure is too serious. Bandaging, especially with rubber bandages, and elevation of the limb, may give temporary relief. Ligature of the artery has been tried and failed.

ATROPHIC CONDITIONS OF THE SKIN.

Besides senile atrophy, in which the skin becomes dry, inelastic, wrinkled, and often pigmented, the following conditions may be described as atrophy of the skin :—

ATROPHODERMA NEURITICA.

This, the "glossy skin" of Paget, follows upon neuritis and other lesions of the nervous system. It is especially well seen in the fingers, of which the skin becomes smooth, shining, dry, the color pink or red, the whole finger tapering, and the nails curved longitudinally and transversely. With this is a severe and persistent burning pain.

STRIE ATROPHICÆ.

These are the translucent, scar-like lines which form in parts of the body which have undergone considerable distention, such as the abdomen after pregnancy (linea gravidarum, linea albicantes), the breasts after lactation, the abdomen, thighs, legs, and arms after extreme anasarca, and the shoulders, breasts and thighs from obesity, or the presence of more localized fatty tumors. A similar change may occur in the skin without any preceding distention, coming on spontaneously and at first without the knowledge of the patient. It is then seen mostly about the buttocks, thighs, knees and ankles, and may be in the form of lines or spots. In all these cases the skin is really atrophied, the papillæ are smaller or absent, the epidermis thinned, and the subcutaneous tissue and glands atrophied. But an early vascular, or even hypertrophic condition, has been observed in idiopathic

cases.

ATROPHODERMA PIGMENTOSA.
(Xeroderma of Kaposi.)

This is a remarkable and rare disease, which consists of combined atrophy of the skin, increased pigmentation, and dilatation of the vessels. It occurs equally in males and females, and has a tendency to affect members of the same family, without being actually hereditary. It begins in childhood, with pigment spots, or with erythematous spots, which soon fade into pigment. These form over the face, neck, scalp in the temporal region, outer side of the arm and forearm, and back of the hand. The pigment spots afterward. become atrophic, and patches of white, depressed, shrunken skin form among them. These white spots are slightly contracted, and difficult to pinch up; and subsequently sufficient tightening of the skin may occur to depress the eyelids, and set up conjunctivitis. On the atrophic area, there occur pink spots of dilated vessels, which gradually enlarge. The disease may remain stationary for a long time, and never spread to other parts of the body; but eventually warty growths develop out of either the dilated vessels or the pigment spots, and these subsequently grow into tumors of an epitheliomatous nature. These fungate, discharge or bleed, and other tumors forming in remote parts of the body, the patient is carried off by exhaustion. No treatment is of any avail.

Kaposi describes a Xeroderma albidum (atrophoderma albidum, Crocker) affecting the leg from the thigh downward, and sometimes the arm down to the hand, in which the skin is atrophied, and then stretched. It begins in early childhood and remains stationary.

ALTERATIONS OF PIGMENT.

Increase of pigmentation arises under circumstances in which hyperemia is induced for a longer or shorter time. The most familiar is exposure to the sun or to the wind; but in the foregoing sections it will have been noticed how frequently pigmentation is said to follow upon the different forms of dermatitis—for instance, eczema, erythema, pemphigus, lichen, and psoriasis; to these may be added erysipelas, syphilitic eruptions, and ulcerations, especially old-standing ulcers from varicose veins in the lower extremities. The application of blisters and mustard plasters is also often followed by staining, a fact which should make one careful how one orders these counter-irritants to the neck or arms of young ladies. Another common traumatic cause of increased pigmentation is the scratching which is indulged in to relieve pruritus, especially that of severe prurigo, whether idiopathic or from the presence of pediculi.

Disorders of the skin in which hyperemia is not a marked feature, are also accompanied with pigmentation, such as scleroderma, Kaposi's xeroderma, and leucoderma, which will be described presently. As a result of internal disease, we see pigmentation of an extreme form in Addison's disease, to a less extent in some cases of lymphadenoma, in the cancerous cachexia, in malaria, and in some cases of tuberculosis. The possibly nervous origin of this has been alluded to under Addison's disease. Except in this last case (melasma suprarenale) it is not common to employ any special name, but the terms melanoderma, and chloasma (from złośę, to be pale green) have been used, of which the former is decidedly preferable. In all the cases which are due to a removable cause, the pigmentation will, in its absence, eventually disappear; on the other hand, it persists in incurable cases like Addison's disease, and increased pigmentation coming on in old age, of course does not undergo any improvement. Local collections of pigment occur, as pigment moles, and pigmented warts. The special forms to be here described are lentigo or ephelis, and chloasma uterinum.

Deficiencies of pigmentation are seen in albinism and leucoderma.

LENTIGO.

(Ephelis. Freckles.)

Yellow, orange, or yellowish-brown maculæ appear on the face, neck, forearms, and backs of the hands, from exposure to the sun under certain conditions. They are most marked during the summer-time, and fade or entirely disappear during the winter; they are first seen about the age of late childhood, and rarely in advanced life, and they affect especially people with fair hair and blue eyes (xanthochroic type). Of a similar kind are the