442 DISEASES OF THE SKIN. 



or " tanned." There is another circumstance, too, which is very diffi 

 cult of explanation, namely, that in certain persons with very white 

 skins, especially in blondes and in red-haired individuals, the pigment 

 formed under the influences just mentioned is only deposited in small 

 circumscribed specks and spots upon the unprotected surface. In 

 summer, the hands, face, and arms of such persons, though screened 

 from the direct rays of the sun, become covered with rounded spots of 

 a more or less dark color, called " freckles " (ephelides). The bronzed 

 skin of a seaman gradually loses its deep color if he stays at home in 

 winter, and, under similar circumstances, freckles also fade or entirely 

 disappear. Freckles may be removed by means of applications capa- 

 ble of producing desquamation of the epidermis, together with its 

 deeper pigmentary layer ; but, if the exciting cause be continued, they 

 will return in course of a few weeks. The well-known Lilionese is 

 merely a palliative cosmetic, as is also the wash recommended by 

 Hebra (hydrarg. chlor. corrosiv. gr. v; aquae | j). The application 

 is only to be kept on for a few hours, and care must be taken that the 

 compress upon which the solution is applied is free from folds. If the 

 skin becomes much inflamed, it is to be covered by compresses dipped 

 in oiL In a few days, as the epidermis scales off, the freckles disap- 

 pear. 



In pregnant women, and women suffering from disease of the sex 

 ual organs, brown spots often appear upon the face, especially upon 

 the forehead and upper lip (chloasmata uterina). In most women they 

 disappear some time after confinement, but in some they are very per- 

 sistent or even become permanent. This phenomenon is as inexplica- 

 ble as is the increase in the pigmentation of the rete Malpighii, and 

 of the areola of the nipples and skin of the linea alba during preg- 

 nancy. 



Besides the diffuse hypertrophy of the papillary portion of the 

 Bkin, which occurs in ichthyosis, hypertrophy of a single papilla, with 

 hyperplasia of the epidermis which covers it, is of very common occur- 

 rence. It is in this manner that warts and condylomata are formed. 

 Warts arise by the elongation and combination of a few papillae, so a? 

 to form a cone. It is covered by a very thick and hard layer of epi 

 dermis. If the several papillae of which the wart consists be each 

 covered separately by its epidermic envelope, the wart has a cloven 

 fibrous appearance. The cause of these growths is unknown. Un- 

 cleanliness of habit certainly plays but a very subordinate role in their 

 production, for, even among the cleanest people, the skin, especially 

 that of the hands, often becomes covered by them in a short time. 

 The sudden manner in which this papillary hypertrophy often disap- 

 pears is equally puzzling. The laity are accustomed to ascribe the 



