8. _Flattening of the muscles_ of those parts on which the body rests, due probably to loss of vital turgidity. 9. _Hypostasis._--Suggillation, or _post-mortem_ staining, is due to the gravitation of the blood to the most dependent parts of the body not subject to direct pressure. The hypostatic marks begin to form in from eight to twelve hours after death, and increase in size till putrefaction sets in. They alter their position with changes in the position of the body so long as the blood remains fluid, but when it has coagulated they remain permanent. Hypostasis may be mistaken for an ecchymosis or a bruise, and in the lungs for congestion, inflammation, &c. Errors may also occur with regard to the brain, stomach, kidneys, and intestines: in the last, the redness of inflammation is seen all over the parts, whereas the coloration of hypostasis is interrupted, and this is best shown by drawing out the convolutions. The heart is an exception to the rule, but it may contain clots varying in size and colour. These are _post-mortem_ formations. The use of the word suggillation is objectionable, as it has been used in opposite senses by Continental and British authors--some writers restricting the term to ecchymosis proper, others using it as synonymous with cadaveric lividity or external hypostasis. Cutaneous Hypostasis (1) _Meaning of the expression._--The gravitation of the blood in the capillaries after death, in obedience to the laws of inert matter. (2) _On what parts of the body usually seen?_--On the most dependent parts of the body; on the whole of the back of the body, if the body be supine. The patches are irregular and slashed, terminate abruptly, and do not fade gradually into the surrounding colourless skin. (3) _At what period after death first observed?_--In from eight to twelve hours, gradually extending in size till putrefaction sets in. (4) _Whether or not affected by death from hæmorrhage?_--Formed after every kind of death, even after death due to hæmorrhage, although the coloration may not be quite so marked. (5) _Hypostasis is liable to be mistaken for ecchymosis--the result of injury._--Hypostasis must also not be confounded with the livid patches seen on the legs and feet of aged persons and on those who have died from typhus, chronic renal and cardiac disease, &c. The rose patches--“frost erythems”--seen on those who have died from exposure to cold, must not be mistaken for ecchymosis. The above patches are as frequently on the upper surfaces of the body as on the lower, and are not so extended as cadaveric lividities; the blood, moreover, which gives rise to them is diffused through the areolar tissue, and not incorporated with the true skin.