Medical Officers of the Army of India.

39

after having been removed from circulation for some time, an occasional flagel-
lated body was seen (Fig. M. 5 and 6 ).

       From 44 to 52 hours new forms were met with, in the act of sporing.
In the case of Lal Khan these were particularly abundant, several could be
seen in each slide made at the pyrexial period; in most cases, however,
they have to be carefully searched for. In these the pigment was con-
centrated in the centre or towards one side, and the appearances were very
similar to those described in the quartan parasite (see Fig. N. 1 to 4 ) The chief
distinctive features are:—1st.—The sporing body is larger, and the spores are
much more abundant, averaging about 20. 2nd. —They are more irregular in
arrangement, and are more rounded. 3rd. —According to many observers, Golgi,
Marchiafava, Mannaberg, etc., they show, as a rule, no detail of structure in the
fresh state. This I have not found to be the case; when fully developed the
nuclear or nucleolar highly refractile spot is distinctly marked.

       The irregular form of sporing described by Golgi was never seen, and, in the
fresh state, the pigment was always seen to be collected into one mass. In
fixed and stained specimens it was frequently found to be irregularly scattered
through the sporing body (Fig. 0. 10 ), but this may probably have been due to
mechanical disturbance while preparing the films. A detailed description of the
relation of the various forms to the course of the fever need not be given. In
all simple tertian cases an invariable connection was found to exist between the
appearance of sporing bodies and the febrile paroxysm, and between the smaller
forms and the early part of the apyrexial period, just as has been described in
the case of quartan fever.

       Quinine apparently acts more slowly in tertian than in quartan fever. In
the latter, 20 grains three times a day during the first and second day prevents
the occurrence of sporulation on the third. In tertian fever, similar treatment
generally modifies the first pyrexial period, producing an abortive but prolonged
rise of temperature, while it appears to entirely prevent a second rise.

       Similar changes to those already described, occur in the parasite under the
action of the drug, the intracorpuscular bodies become stunted and necrotic in
appearance during the first two days, a few form irregular spores, and on the
third day no abnormal element is to be found in the peripheric blood save a few
spheres and pigmented phagocytes.

       Structure of the Parasite of Tertian Fever. —The tertian parasite, owing
to its large size, lends itself specially well to the study of the morphological
characters of the class. To bring out these characters it is necessary to care-
fully stain thin films of the blood which have been rapidly and accurately fixed.
Many stains have been recommended by various workers, the hæmatoxylin stain
of Mannaberg, used after fixing the films with his special picric acid solution
gives good results, but I have found none more satisfactory than staining