Under this head we include all those products of serous, albuminous, pasty, fibrinous, puriform, and purulent exudation occurring on the mucous membrane, which are more or less profuse, and are preceded by slight redness and congestion. Maceration and solution of the epithelium, relaxation, and infiltration of the mucous and submucous tissues, fusion (as it were self-secretion) and gradual disappearance of the mucous membrane and its follicles, take place at the same time. The mucous membrane is softened and tumid, it is infiltrated with the exuded matter, variously reddened and injected, or pale, or of a dirty gray or tawny color. In proportion to the degree of vascularity and the quality of the exudation, it is more or less pultaceous, and attenuated or entirely destroyed.

We here also adduce the process that takes place on the intestinal mucous membrane in cholera, the acute pituitous condition of the mucous membrane (Eisenmann's pyrotic process), genuine croup, puriform and purulent diarrhoeas, etc.

These processes probably always involve a large tract of intestine, and are the expression of a constitutional affection, which itself may either be primary or secondary; in the latter case it represents a degeneration or an anomalous form of the original disease. The not unfrequent degenerations of specific cachexia, such as typhus, the exanthemata (particularly variola and scarlatina), acute tubercle and cancer, which were originally acute, or have become so under certain conditions, may thus present the type of the process just described.