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sexual form produced by ‘ gametoschizogony ’ 840 or 14,000 spores. 
Until better evidence for such views is adduced, our results justify 
the doctrine that the malarial infection is kept continuously alive 
simply by the persistence of the asexual form in varying numbers; 
and that fever occurs only when the forms are numerous enough to 
produce it. 
9. The effect of quinine on the asexual forms. The destructive 
effect of the drug is of course everywhere recognised, though very 
Tittle completely satisfactory statistical evidence can be cited in proof. 
Many laborious researches have been made regarding the comparative 
utility of the various salts, but these have been confined almost 
entirely to estimating the rate and percentage of absorption, judged 
from urinary elimination. The subject is of the greatest sanitary 
and medical importance ; but, so far as we can see, it can be usefully 
studied only by the more detailed enumerative analysis which we 
propose soon to undertake. Our daily analysis gives little more light; 
but the following figures may be mentioned. Cases 1 5 > *6 
showed no asexual forms; Cases 11 and 13 were so severe that 
quinine was given at once; Cases 1, 5, 27, 31 and 32 were so mild 
that quinine was withheld during the period of observation ; and 
in the remaining cases the drug was withheld only for some days 
(except an occasional necessary dose) and was then given continuously 
while the parasites were being counted. We have therefore added 
together all the daily counts during the periods of no-quinine and 
quinine respectively. With eight cases of P. vivax there were 
forty-five no-quinine days showing 104,032 total parasites, or an 
average of 2,312 a day; and there were 74 quinine days with 
3U769 total parasites, or an average of only 429 a day (one-fifth). 
With P. falciparum (19 cases), 147 no-quinine days showed an 
average of 31,136 asexual forms, and 148 quinine days an 
average of 1,535 (one-half). We should have expected that 
the proportion of quinine-day parasites would have been 
smaller; but the no-quinine counts are diminished by the inclusion 
of the five mild cases and also by doses of 10 to 20 grains 
which were given on ten isolated occasions. On quinine days the 
doses are generally 20 to 30 grains a day, and Cases 11, 1 3 > * 4 > 
a nd 16 and parts of other cases are omitted because they were 
unsuitable. Great falls in the number of parasites occurred, even 
