321 
reached the high figure of 4'i grams (following three days’ constipa¬ 
tion). Some stools were unfortunately lost, but his total urobilin 
output (urinary and faecal) amounted to 6'8 grams, which represents 
20 per cent, of his total normal haemoglobin. 
The haemoglobinometer readings fell 25 per cent., of which 15 per 
cent, was regained within a week. His urobilin output corresponds 
to a destruction of 1,000,000 corpuscles per mm. 3 , while the maximum 
number of parasites seen in rhe peripheral blood was 35,000 per mm A 
V. SUMMARY 
There can therefore be little doubt that, in malignant tertian 
(P. falciparum ) infection, the excretion of haemoglobin derivatives 
is much higher than in other diseases with a similar degree of 
pyrexia ; this excretion is accompanied by, and probably depends on, 
a fall in the haemoglobin present in the circulating blood, and would 
seem to demonstrate that the fall in the haemoglobinometer readings 
represents an actual destruction of red blood cells, not merely an 
alteration in the relative proportions of corpuscles and plasma in the 
peripheral blood. 
In Cases 21 and 23, respectively, thirty-five and twenty-five 
corpuscles at least must have been destroyed for every parasite 
present, and this suggests either that the corpuscles are disintegrated 
mechanically (or as part of a protective mechanism) by the efforts of 
the spores to enter them, or else that the mother-parasite contains 
some haemolytic substance which is liberated on sporulation. 
Finally I would like to draw attention to the relationship between 
the elimination by the urinary and faecal channels in these cases, 
and, indeed, in health and in other diseases. Only exceptionally 
does the urinary output approach the level of the faecal output, and 
yet practically all the quantitative work that has so far been done 
on urobilin, has been confined to the small and comparatively 
unimportant channel. 
Before concluding I would like to refer to the eighth case of 
malignant tertian infection mentioned in dealing with faecal urobilin, 
and which, owing to its peculiar interest, is dealt with in a separate 
paper by Major Ross, Dr. Thomson and myself (p. 3 ° 7 )- 
When admitted to the hospital he had a fairly severe attack of 
malignant tertian malaria, and in the week following its onset he 
