In scarlet fever, the morbid changes are somewhat different. The mucous membrane covering the trachea, the larynx with its cartilages, the amygdalæ and the soft palate is inflamed; the redness is of a brighter and more vivid colour than that which has been stated to be characteristic of continued fever without an eruption: it is similar to the characteristic colour of the scarlatina tongue. But what is very remarkable, and what appears to justify the view we have taken of scarlatina and the division we have suggested of its types, when the cases are severe, the colour of the mucous membrane becomes much darker, the deepness of the tinge increasing with the severity of the affection, until, at length, the colour closely resembles that which is peculiar to ordinary fever. As in continued fever without an eruption, so in scarlatina, the increased vascularity of the mucous membrane is accompanied with a preternatural thickening of its substance. In scarlet fever, that portion of it which covers the epiglottis, the rima glottidis, and the arytænoid cartilages, is especially found in this diseased condition. When this inflammation and thickening passes into the state of ulceration, which it often does, the arytænoid cartilages are the special seat of this process, although the ulceration often extends to the amygdalæ, and sometimes to the root of the tongue. When in every other respect healthy, the substance of the lungs in fever is so constantly found either engorged with blood or infiltrated with serum, that these changes would seem to form essential parts of the morbid phenomena. In examining those who die of fever, a great variety and complication of thoracic diseases, in addition to the morbid changes just described, are found. The pleuræ exhibit every degree of vascularity, from the faintest blush of redness to that which is characteristic of the most intense inflammation, and every extent of adhesion, from that of the smallest point to the complete obliteration of the cavity. The usual products of inflammation, namely, the effusion of serum and lymph, and the formation of pus and of adventitious membrane are likewise found equally varying in degree. The parenchyma of the lungs, besides the engorgement and infiltration just adverted to, presents hepatization and tubercular disease in every variety and degree; ulceration and abscess in every extent, and hæmorrhagic and calcareous depositions, together with enlargement and melanosis of the bronchial glands. But, since none of these diseases form any part of the changes of structure which are peculiar to the febrile state, it is sufficient in this place merely to advert to them. 4. _Morbid Appearances in the Abdomen._