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     If, after washing, the section is dark purple or blue, wash in 1 to 400 acetic
acid in distilled water, and at once plunge into water. The acetic acid removes
the excess of methylene blue staining and makes the tissue much clearer. If too
long washing is given, the red colour will also be removed, If the section is
light reddish or light purple after washing with alcohol the acetic acid bath is
unnecessary.

     Allow the section to dry upon the slide. It is on account of the necessity
for this procedure that thin sections must be used. In the case of very thin
sections shrinkage is negligable, but in thick sections it is considerable.

     Mount in Canada balsam or keep as a film and examine merely by placing a
drop of cedar oil on the section.

     Quite unshrunken tissues may be examined after staining by washing and
mounting in glycerine. The result is useless as a permanent preparation since
the glycerine dissolves out the red stain, but it is useful for temporarily displaying
the relation of parasites to the tissues.

     Several kinds of tissues may be examined in this way, and the parasites
displayed by spreading portions of the tissues upon a slide, drying, fixing in
alcohol, and staining as above. Omentum, teased muscle, connective and other
tissues give good results. Micro-organisms are very well shown when present.

     The changes in the organs and the distribution of the parasite in the tissues
were similar in all three fatal cases.

     Films made from the liver substance showed many bodies free and in
leucocytes. The most striking feature was the presence of large leucocytic cells
crowded with the bodies. The liver cells were free from parasites.

     Sections of the liver showed very clearly the relation of the parasites to the
tissues. The lobular capillaries were dilated and the liver cells, especially in
certain areas, were much atrophied. In the capillaries were seen numerous large
cells crowded with parasites. The bodies of these cells were usually situated in
the lumen of the capillary, but attached by several processes to the capillary wall.
In many cases they were applied closely and flattened against the capillary wall.
The protoplasm of these cells was often retracted so as to form a globular mass,
but more usually was stretched out along the capillary in a very characteristic
way. The appearance of these cells irresistibly suggests large amœbæ crawling
about the capillaries. In some parts of the sections these cells were extremely
numerous, forming the bulk of the tissue. In one of the cases the cells were
so crowded with bodies that their nuclei were often hidden. The exact nature
of these large cells is doubtful, but they appear to be identical with the large