In ecchymosis the blood capillaries being ruptured, the blood permeates the bruised tissues surrounding the ruptured vessels and thus gives the characteristic color of venous blood. There seems to be no positive treatment, but in some cases it can be remedied to some degree by a hypodermic injection of a good bleacher, and then massaging the part with a strong bleaching solution. Spots of this kind can sometimes be covered with flesh tints. It is often important to determine whether violence has been inflicted on a body before death. In regard to this point, we must remember, first, that blows and falls of sufficient violence to fracture bones and rupture the viscera may leave no marks on the skin, even though the person has survived for several days; and, second, that there are postmortem appearances which simulate antemortem bruises. A severe contusion during life may present, at first, no mark or only a general redness. After a short time the injured part becomes swollen and of a red color, this color may be succeeded by a dark blue, and this in turn fade into a greenish yellow or yellow; these later appearances are due to an escape of blood from the vessels and to a subsequent decomposition of the hemoglobin. If, therefore, we cut into such an ecchymosis after death, we find extravasated blood or the coloring matter of the blood, in the form of pigment granules, free in the tissues. Postmortem discolorations, on the other hand, although their external appearance may resemble that of antemortem ecchymosis, are not formed by an extravasation of blood, but by a circumscribed congestion of the vessels or by an escape of blood stained serum. If you cut into such discolorations, therefore, we find no blood outside the vessels. Care should be taken not to mistake the lesions of hemorrhagic infection for traumatic ecchymosis. Blows on the skin of a body which has been dead for not more than two hours may produce true ecchymosis with extravasation of blood, such as can be distinguished with great difficulty or not at all from those formed during life. If putrefactive changes be present, the difficulty of distinguishing between antemortem and postmortem bruises is greatly enhanced. Hanging and strangulation are attended with the formation of marks on the neck which are described in works on forensic medicine. These marks must not be confounded with the natural creases of the skin of the neck. Many adults during life have creases of the skin of the neck, one or more in number, running downward from the ear under the chin or encircling the neck. After death these creases may be much more evident than during life, and may be rendered more decided by the position of the head, or if the body be frozen. They usually persist until the skin putrefies.