Suppuration takes place here with a rapidity of which we have an example in but few of the organs. Every one knows the fluid that comes from this suppuration. Its colour, its consistence, all its external qualities have become the type to which we refer the ideas that we form of pus; so that that which does not resemble it, is considered to be pus of a bad kind, or as we say sanious. This opinion is incorrect. Certainly the pus that flows from a bone, a muscle, the skin in erisypelas, the mucous membranes in catarrh, is of a good kind so long as the inflammation is regularly going through its periods; it is however totally different from cellular pus. As this is most frequently observed, especially in surgery, we have formed a general idea of laudable, as of sanious pus. Cutaneous, mucous, osseous pus, &c. have each their peculiar sanies, which differs among them according to the vital alterations of the organ, from which it is derived. So that the pus of each system differs from that of the others, in the same way as the alterations of which it is susceptible are different from their purulent alterations. Has the cellular texture peculiar vital modifications in those organs to whose structure it contributes? From what has been said above, it seems hardly probable. All that I have been saying, applies to the system considered in the interstices of the organs, separate from all combination with their structure. It is possible however that its vital activity is diminished in the cartilages, the tendons, &c., that it is increased a little in the skin, that its life, in general tends to an equilibrium with that of the parts in which it is found; but these are conjectures that nothing positive confirms. That which ought not to escape us here, is the manifest difference of vitality that exists between the texture of layers and filaments almost every where spread, and the texture that is wholly filamentous, which is exterior to the mucous surfaces, to the blood-vessels, and excretories, a difference from which arises the rareness of inflammation and tumours in this last. It is often a real barrier that stops the affections of the first, a barrier that protects the organ it covers. Thus I have many times observed in opening bodies, that whilst the ordinary texture, in which the arteries are embedded as in the axilla, is in a state of suppuration, and almost disorganized by the pus, that which forms the external covering of the vessels remains untouched; it has not undergone the least alteration. I have seen the same phenomenon in the texture exterior to the urethra in deposits of pus at the loins. III. _Properties of re-production._ The cellular texture is distinguished from other organs by the faculty it has of throwing out a kind of vegetation, of elongating and re-producing itself, of growing when it has been cut or divided in any manner. It is upon this faculty that depends the formation of cicatrices, tumours, cysts, &c.