Fig. 32.—Body of a female undergoing decomposition.
patches also make their appearance successively on the chest, neck, face,
arms and legs. These patches gradually deepen in colour, and later become
purple and dark blue. They are at first separate and distinct, but later on
coalesce together, and the whole skin of the body appears discoloured.
Soon after the discoloration of the skin has commenced the superficial
veins look very prominent like purplish red or green streaks owing to the
decomposed blood setting free the colouring matter of the red blood cor-
puscles, which stains the walls of the blood vessels and infiltrates into the
tissues, which also appear coloured. The clotted blood becomes fluid; hence
the position of post-mortem staining is altered, and the fluid blood collects
in the serous cavities, especially in the pleurae and pericardium.
Development of Foul-smelling Gases.-^Side by side with the appearance
of the greenish patch on the abdomen the body begins to emit a nauseating
and unpleasant smell owing to gradual development of the gases of decom-
position, some of which are sulphuretted hydrogen, marsh gas, carbon 1
dioxide, ammonia and phosphoretted hydrogen. *
From twelve to eighteen hours after death in summer these gases collect
in the intestine ; consequently the abdomen swells up. The sphincters relax,
and the urine and faeces may escape.
Jiom eighteen to thirty-six or forty-eight hours after death the gases
collect in the tissues, cavities and hollow viscera under considerable pressure
•with the result that the features become bloated and distorted, the eyes are
forced out of their sockets, the tongue is protruded between the teeth, and
the lips become swollen and everted. A frothy, reddish fluid or niucus is
forced from the mouth and nostrils. Ultimately the features become
obliterated and unrecognizable. .JJje abdomen becomes greatly distended;
hence on opening the cavity the gas escapes with a loud explosive noise.
Owing to the pressure of the gases the stomach contents are forced into the
mouth and larynx and are seen running out of the mouth and nostrils. The