26. After a moderately severe infection there is a formation of transparent, submiliary eruptions (nowadays our “gray miliary tubercle”), especially about the smallest vessels of serous membranes. _These eruptions are capable of becoming organized. In fact, when they have healed they form a tissue entirely identical with the tissue in which they originated._ (Bichat, Lebert, Empis, and many other older investigators.) Aufrecht, _Deutsch. Arch. f. klin. Med._, Vol. LXXV. 27. The introduction of a tubercular virus so strong as to cause the smallest vessels to become occluded, especially Cohnheim’s terminal arteries of the spleen, lungs, and kidneys, results in the exudation of a coagulable fluid and in necrobiosis of the extra-vascular region supplied by those vessels. (Aufrecht, _Arch. f. klin. Med._, Vol. LXXV.) Into this dead area tubercle bacilli are dragged by the wandering cells. These bacilli multiply and cause chemical changes which manifest themselves first in a fatty (steatomatous) and then in a cheesy metamorphosis. (Cf. Koch, Volume II of the _Mittheilungen aus dem Kaiserlich. Gesundheitsamt_, p. 21, and Plate IX, Figs. 45 and 46); my own observations; Aufrecht, 1. c.; compare also the critical reference by Virchow to the works of older authors, such as Vetter, Gendrin, Lobstein, Cruveilhier, Bayle, Baillie, Laënnec, Rilliet and Barthez, Vulpian, Craigie, etc., in “Phymatie, Tuberculose und Granulie,” and in Vol. II of “Die Krankhaften Geschwülste.” 28. We may enumerate as the result of primary tubercular focal disease (_a_) Anatomically demonstrable residues. (_b_) Functional alterations. 29. Functional alterations may remain without any anatomically demonstrable residues of the primary infectious processes. I divide functional alterations into (_a_) Alterations which leave behind them an immunity against living Tb. virus, probably to be sought for in the peculiar condition of the vessel musculature and, in the beginning at least, always associated with hypersensitiveness to the soluble tubercular poisons. (_b_) Scrofulous diathesis, consisting in such changes in the vascular system and the lymphatic apparatus that a renewed Tb. infection very readily causes cheesy tubercular lesions. 30. As scrofulous infectious processes, I regard (_a_) Lupus, which I interpret as a cutaneous additional effect of a tubercular infection. (_b_) Gland scrofula,[6] inclusive of tuberculosis of the mediastinal, bronchial, and mesenteric glands. (_c_) Bone scrofula and joint scrofula. (_d_) Scrofula in the domain of the external body covering, of the mucous membranes, and of the lymph-channels. (_e_) Cheesy metamorphosis in internal organs, inclusive of the organs of sense, and the vessel intima.