The place of its typical occurrence is the thyroid body in certain cases of goitre, and it is early met with as a homogeneous substance replacing the granular cell-protoplasm. With its increase the latter disappears, and the entire cell is transformed into a homogeneous sphere. At times the colloid substance may be seen to project from the surface of the cell as a pale rounded clump. The aggregation of these clumps results in the presence of masses of various size, in which may be found granules of fat or pigment and crystals of cholesterin, which are accidental, not essential. Colloid masses are sometimes met with--in lymphatic glands, for instance--as concretions, mulberry-like aggregations of stratified colloid bodies, which may be infiltrated with earthy salts. Colloid material may eventually become liquefied, transformed into a sodium albuminate; and the presence of cysts in certain varieties of goitre is thus explained. The coexistence in the kidney of colloid accumulations and watery cysts has led to the view that the latter may, under certain circumstances, result from the former through the liquefaction of the colloid material. The same view is held with regard to the origin of cysts frequently met with in the choroid plexuses. The colloid metamorphosis of cells is also to be found in the epithelium of mucous membranes and their glands, in the prostate, suprarenal capsule, sebaceous glands of the skin, and in the cells of certain tumors. _Amyloid Degeneration, Amyloid Infiltration, Waxy Degeneration, Lardaceous Degeneration._ The colloid appearances due to the amyloid degeneration of cells are of the greatest clinical importance from their frequent occurrence and the gravity of the symptoms connected with their presence. In amyloid degeneration there is the transformation of the cell-protoplasm into an albuminous material different from other albuminates found in the body. This transformation is at the expense of the functional activity of the cell, and the latter becomes inert. Amyloid degeneration represents no mere substitution, but an addition, since the affected tissue is increased in volume. The albuminate was called amyloid by Virchow in consequence of its color-reaction with iodine. Its method of origin is wholly unknown, never being found in the circulating fluids nor in articles of food. It is met with chiefly in the cell, although its presence in the intercellular substance of old people is recognized, and its occurrence in {85} the midst of the thrombotic deposition on inflamed valves and in the results of inflammatory processes is also recorded.