The skin is liable to be affected in three different forms. (See Cases I, II, III, IX, X, and XXXIV). The first of these occurs very rarely, and consists of small deposits of matter in the structure, or upon the surface of the skin, resembling in many respects the pustules of small-pox. The second form is also of rare occurrence, and consists of small congested spots on the surface of the skin. These are generally of a dark purple hue, but I have seen one case in which they were of a bright red colour. In this instance, a secondary abscess had formed in the knee-joint, and some pustules appeared upon the skin in the neighbourhood. A fortnight before the death of the patient, a number of small bright red spots made their appearance in different parts of the thigh and upper part of the leg; some of these were three or four lines in diameter while others were so small as not to be seen without attention; they appeared in accurately defined spots, of a brighter colour than the mucous membrane of the lips, and continued unchanged in appearance till death. The third form presents itself much more frequently than either of the others, although it has not hitherto much attracted the attention of pathologists, in connexion with purulent or other infection of the blood. It commences very suddenly, and frequently without any particular attention being directed to the part. A large circular patch of congestion, livid or purple in the centre, but becoming of a lighter colour towards the circumference, will form, usually upon some part of the lower extremities. The skin of the calf of the leg is perhaps more frequently attacked than that of any other part. In the centre of the congested portion, mortification very rapidly takes place, and is indicated by the part assuming a black or dull leaden colour. In some cases, it would be difficult to say where the mortification ceases, and the congestion begins; but in other instances, there is a distinct line of demarcation formed: a zone of bright red congestion will then occasionally surround the mortified part. Some modifications of this third form of affection of the skin may be met with occasionally in the course of the disease. Blotches assuming a livid or dusky red appearance (which gradually fades into the colour of the surrounding skin), will present themselves in different parts (Case XXXVI), and terminate in thick exfoliation of the cuticle, or in small sloughs of the skin. In some instances, the superficial portions only of the skin are destroyed, and the parts beneath appear comparatively unaffected; small circumscribed portions of the outer layer of the skin will exfoliate, and the subjacent parts will heal without suppuration, by a process similar to that of scabbing (Case III).