The granular degenerations of the heart, liver, and kidneys, as a whole, usually occur simultaneously, and afford a most important means for the post-mortem recognition of the infective diseases. The condition is therefore to be looked for in the exanthemata, especially in small-pox and scarlet fever, also in erysipelas, septicæmia in its manifold forms, diphtheria, typhoid and typhus fevers, cerebro-spinal meningitis, etc. A common feature in all these cases is the occurrence of fever, and it has been claimed that this element is the cause of the degeneration. In opposition to this view is the well-known fact of its presence in afebrile cases of poisoning from carbonic oxide, and its absence in certain cases of pneumonia and exposure to high temperatures. The universal occurrence of cloudy swelling in fatal cases of the affections above mentioned leads to the inference of its presence in those instances terminating in recovery without obvious permanent impairment of the organs and tissues concerned. It is therefore agreed that the process may terminate in resolution--_i.e._ in a disappearance of the excess of granular material. On the other hand, its association, under circumstances, with fatty degeneration suggests as extremely probable that the latter condition may represent a result of the albuminoid infiltration. Even if this more serious issue exists, the possibilities are still at hand for an absorption of the degenerated material and a restitution of the destroyed protoplasm. The effect upon the individual is evidently determined by the persistence and dissemination of the condition, which, in turn, are controlled by the immediate cause and the peculiarities of the individual acted upon. _Fatty Metamorphosis, Fatty Degeneration, and Fatty Infiltration._ The fat which is present within the body under physiological conditions owes its origin primarily to the food taken. A diet which is abundantly fatty furnishes a direct source for much of the fat which appears accumulated in the various organs and tissues. Although it may now appear that such a statement needs but little confirmation, it is not long since the opinion prevailed that nearly all the fat in the body came from the hydrocarbons of the food. This seemed all the more plausible as the herbivora readily accumulated fat, although their diet might contain this element in very small quantities. Hofmann[29] made a decisive experiment with reference to the origin of fat from fatty food by feeding a dog, made lean by starvation, with bacon in abundance, but with little meat. In the course of a few days the greater part of the fat introduced was deposited within the tissues of the animal. Other experimenters have arrived at a similar result, and it can no longer be questioned that fat, accumulated within the body, owes its origin chiefly to the absorption of fat from the food taken. [Footnote 29: _Zeitschrift für Biologie_, 1872, viii. 153.]