The =nails= should be considered in connection with skin and hair, with reference to the following points: presence or absence, hypertrophy, atrophy, color, condition, length, development, onychia, hyperonychia, paronchyia, onychogryphosis, longitudinal and transverse ridges, fissures and cracks, opacity, brittleness, etc. 25. =Teeth.= Number, character, condition, anomalies, dental work, caries, Hutchinson’s teeth, odontoma, dental osteoma, dentigerous cysts, epulis, papilloma, etc. 26. =Mucous Membranes.= Color, deposits or incrustations, eruptions, erosions, herpes, mucous patches, rhagades, ulcers, fissures, moisture, trauma, effects of corrosives, burns, pigmentation, as in Addison’s disease, leukoplakia, hairy tongue, hemorrhages, tumors, etc. 27. =Muscles.= Musculature and condition of muscles (slight, athletic, well developed, poor, flabby, soft, etc.), anomalies, etc. 28. =Rigor Mortis.= Postmortem rigidity is one of the absolute signs of death. It begins usually 1-2 hours after death, the involuntary muscles and heart showing it first. Externally it shows first in the muscles of lower jaw and neck, extends downward, involving the lower extremities last and disappearing in the same order. Its appearance, however, is subject to the greatest variation, and the presence or absence of rigor mortis cannot be used as a criterion for the estimation of the length of time the body has been dead. Instantaneous rigor has been reported in suicides and in people killed in battle. Intense excitement, great muscular exertion, etc., favor its rapid appearance. It also comes on very quickly after death from rabies, tetanus, strychnine poisoning, cholera and a number of other conditions. It sometimes is delayed or absent after heat-stroke; chronic alcoholism also delays its appearance. Usually the contraction lasts 24-48 hours, but under certain conditions may persist for several days. It is prolonged in muscular individuals, after death by suffocation, rabies, strychnine poisoning, etc. The stiffening of the muscles may be broken by application of heat or the use of force (removal of clothes from the body); when once broken it rarely returns. In a case of death from rabies seen by the writer the rigor was so strong that it required the united efforts of two men to straighten the limbs, and before the close of the autopsy the rigor had returned as strong as in the beginning. Rigidity due to undertaker’s injections and freezing must not be mistaken for rigor mortis. The possibility of rigidity due to ankylosis must also be borne in mind.