In the typhoidal inflammations are associated those symptoms which are so prominent in the severe varieties of typhoid fever. These are the predominant symptoms: hebetude or low, muttering delirium, picking at the bed-clothes, involuntary evacuations, stertor, and the like. The nervous disturbances are associated with a feeble pulse and a dusky hue of the skin. The constituents of an inflammatory exudation are frequently used as a basis of classification, and characterize the inflammation from the anatomical point of view. As the exudation is complex in its composition, the predominant element is made use of to designate the variety, and in doubtful cases a combined adjective indicates the presence of the two most abundant constituents. As the exudation is directly derived from the blood and contains serum in addition to white and red corpuscles, the serous, purulent, and hemorrhagic varieties of exudation naturally arise. The fibrinous and diphtheritic inflammations relate to the presence of membranes or false membranes. Finally, there are the productive inflammations, resulting in the new formation of tissue, and the destructive inflammations, where losses of substance occur. Serous inflammations are most frequent in those parts of the body where the structure contains the largest lymph-spaces. The so-called serous cavities of the body offer the most favorable opportunities for the accumulation, as well as for the exudation, of the inflammatory product; then follow the regions of the larger lymph-spaces, according to the size and number of the latter. The serous inflammations may also arise from the epithelial coverings of the body, as the cutaneous, alimentary, and respiratory surfaces. The serous exudations of the skin are those present in vesicles, blisters, or bullæ, which owe their limitation to the resistance offered to the spreading of the liquid inflammatory product by the coherent epidermis. Serous inflammations of the alimentary canal may assume a vesicular character, although, from the structure of its mucous membrane and the macerating influence of its contents, the vesicles are apt to be of an extremely transitory character. The more important serous inflammations of the intestines are those manifested by profuse watery evacuations, the extreme form of which is to be found in cholera. Serous inflammation of the lungs accompanies the more severe forms, and usually represents but a limited and circumscribed affection, associated with more abundant cellular and fibrinous products. Serous inflammations of the peritoneum, pleura, pericardium, tunica vaginalis, and central ventricles often give rise to the presence of enormous quantities of fluid, whose partial removal from many of the cavities concerned by operative measures frequently represents a most beneficial result of treatment.