Appx. XXI.

Specimens for laboratory examination.

of the type of cellular exudate. No pressure should be used for spread-
ing this film or the cells will be broken down. A useful method is to
place some mucus on a piece of litmus paper used for testing the reaction
of the stool and draw the mucus along the slide. The reaction of the
mucus and the time and date on which the stool was passed should
be invariably entered on the laboratory report.

     Instructions should be given to subordinates that in cases suspected
of suffering from dysentery a clean dry bedpan free of antiseptics
should be used and also that patients should first pass their urine into
a separate receptacle in order that no urine should be mixed with the
stool in the bed pan.

     8. Amoebic dysentery—E. histolytica begins to degenerate directly
it leaves the intestine. Movement ceases as a rule after one hour and
diagnosis frequently becomes impossible. In cases in which amoebic
dysentery is suspected, but in which it is impossible for the specimen
to reach the laboratory within at the latest two hours after being
passed, mucus (preferably blood stained) should be spread on three
coverslips. Before the films dry the coverslips should be dropped
film surface down into Schaudinn's solution and left for fifteen
minutes. They should then be transferred to a small bottle con-
taining 70 per cent. alcohol (with a little cotton wool at the bottom
of the bottle to avoid breakage in transit) and be forwarded to the
laboratory.

Schaudinn's solution.

     In every case a dried film of mucus prepared as described above in
para. 7 should be forwarded for examination of the cellular exudate.

     Fæces for examination, for cysts should be selected not from loose
stools but from solid fæces, which should be thoroughly emulsified
in Weigert's iodine solution and forwarded to the laboratory.

Weigert's iodine solution.

   N.B. —Cysts are not found in cases of acute dysentery.

     9. Stools should be forwarded daily to the laboratory until a
positive result is obtained or until information has been received from
the D. A. D. P. that further specimens are not required.

     10. In every case of dysentery medical officers should take the
opportunity of examining specimens of mucus in the clinical side

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