1910.| Some Enumerative Studies on Malarial Fever. 163 
or followed by apyrexia, and in all, except Case 32, the asexual parasites 
were very much more numerous during the pyrexial period. Nine of the. 
cases (7, 17, 18, 19, 20, 23, 24, 26, 32) suffered from one or two relapses 
each (15 relapses altogether), and every relapse, as ‘well as every original — 
attack, was associated with a comparatively large number of parasites 
(43 pyrexial periods altogether). Similarly, there were 46 apyrexial periods 
(including the four cases without fever), all associated with comparatively . 
small numbers of asexual parasites, and conversely not a single marked rise 
in the number of asexual parasites took place without corresponding fever. 
For further detail we compare the numbers of parasites per cubic milli- 
metre counted on days of fever with those counted on days without fever. 
A febrile day is taken as any one on which the patient’s temperature exceeds 
98°°6 F. (= 36° hematometric scale), or any one which comes between two 
tertian paroxysms (Cases 9, 14, 24). The non-febrile days on which no 
asexual forms could be found in 1 cu. mm. of blood are omitted. The results 
are— 
| 
Cases. Days. Hoa NIE SN ee Ratio. | 
parasites. day. . | 
P. vac. i 7 
ISG? BBG es nee: eee ene 8 | 30 136,062 4,535 36-3 
INOS AGE Ne Sets er ee 8 | 68 | 8,487 | 125 | 
P. falciparum. 
Saicie’ Q ae ae eed 21 97 | 1,819,880 "18,607 mee 
INCOME VON hE NA. oh few dies vs 19 83 | 38,277 | 461 
| 
If we had not omitted the non-febrile days on which no parasites were 
found, the non-febrile daily averages would have been much smaller than 
the figures given above, and the ratio of the febrile averages to them much 
larger, so that the febrile excess is very marked. An examination of the 
details wili further convince the reader of the great fall in temperature 
which accompanies the fall in the number of parasites. We should note 
that the comparatively small numbers of P. vivav found are due to the fact 
that the specimens generally contained a large proportion of mature 
parasites, not as yet disintegrated into spores, these of course being absent 
from peripheral blood containing P. falciparum, in which only spores or 
young forms generally occur. There is no reason for considering quinine 
in this connection, because it probably affects the fever only through its 
action on the parasites. ‘ 
