140 BACTERIOLOGICAL DIAGNOSIS. 
COLLECTION OF MATERIAL AT POST- 
MORTEM EXAMINATIONS. 
The saprophytic bacteria which occur in such vast 
numbers in the skin and alimentary canal during life 
undergo very rapid multiplication after death; hence, 
in cases where bacteriological examinations have to be 
made the sectio should be performed as soon as possible 
after death. 
The materials which should be examined in all cases 
are the heart-blood, the spleen, and the liver, and the 
following methods are to be employed. 
The heart-blood should be collected in the method 
which has been described previously (see p. 42), and 
cultures may be made upon the spot, or the pipettes 
sent to a laboratory. : 
The spleen may usually be examined in the same way. 
If it is so firm and hard that no fluid rises into the pipette, 
it should be treated in the same way as the liver. 
Cultivations should be made from the diver at the 
time when the autopsy is performed. The organ 
should be cut in half, anda small portion of the cut 
surface deeply seared with a hot iron. This area is 
then to be perforated with a stout platinum needle and 
the culture media inoculated at once. 
If the material has to be sent to a distance and no 
culture tubes are at hand a different course must be 
adopted. The simplest way is to cut out a cube of 
liver substance from the centre of the organ, and to sear 
every part of its surface with the flat of a red hot knife. 
The block (which may be about as large as a lump of 
sugar) must be dropped at once into a sterilised bottle 
and sent to the laboratory where the examination is to 
be made. Another plan is to sear the surface of the 
