It is usually superficial, has thin, red, undermined edges of a violaceous color, and an irregular base with granulations covered scantily with pus. As a rule, it spreads gradually as a simple ulceration, with but slight, if any, outlying infiltration. Subjective symptoms of a painful or troublesome character are rarely present. Its course is usually progressive but slow and chronic. Other symptoms of tuberculosis are commonly to be found. #Are other forms of tuberculosis cutis met with?# A papulo-pustular eruption is sometimes observed, especially on the upper extremities and face; sluggish and chronic in character and leaving small pit-like scars; has been known as the _small pustular scrofuloderma_. [Illustration: Fig. 49. Tuberculosis Verrucosa Cutis (patient had a coexistent pulmonary tuberculosis).] An ulcerative papillomatous or verrucous tuberculosis of the skin (tuberculosis verrucosa cutis) is also occasionally noted, most commonly seated upon the lower leg or the back of the hand. It may be slight or extensive. Its mildest phase is the so-called verruca necrogenica. #Describe verruca necrogenica.# Verruca necrogenica is a rare, localized, papillary or wart-like formation, occurring usually about the knuckles or other parts of the hand. It begins, as a rule, as a small, papule-like growth, increasing gradually in area, and when well advanced appears as a pea, dime-sized or larger, somewhat inflammatory, elevated, flat, warty mass, with usually a tendency to slight pus-formation between the hypertrophied papillae; the surface may be horny or it may be crusted. It tends to enlarge slowly and is usually persistent, but it at times undergoes involution. [Illustration: Fig. 50. Tuberculosis Cutis (Verruca Necrogenica). (_After Model in Guy's Museum._)] #State the etiology.# Heredity, insufficient and unwholesome food, impure air, and the like are predisposing. The tubercle bacillus is the immediate exciting cause. The disease usually appears in childhood or early adult life, and not infrequently follows in the wake of some severe systemic disease. Etiologically it is identical in nature with lupus. #How is the tuberculous ulcer to be differentiated from syphilis?# By the peculiar character of the tuberculous ulceration, the absence of outlying tubercles and infiltration, together with its history, course, and often the presence of other tuberculous symptoms. #State the prognosis.# These various types of tuberculosis cutis are, as a rule, more amenable to treatment than that form known as lupus vulgaris (_q. v._). #What is the treatment of these forms of tuberculosis cutis?# Constitutional remedies, such as cod-liver oil, iodide of iron or other ferruginous tonics, together with good food and pure air; phosphorus one-hundredth to one-fiftieth of a grain three times daily is also of benefit in some cases.