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IV] parasite in the general circulation as represented by finger blood. They show that what is seen in finger blood does not represent anything like the aggregate mortality that is going on among the corpuscles from direct destruction. The principal part of the malarial drama is played out in the spleen, liver, bone marrow, brain, etc., and not in the general circulation. What is seen in finger blood is but an overflow, as it were, of the greater drama going forward in the viscera.

The yellow pigment.—— Besides the pathognomonic black pigment (hæmozoin), there is usually found in the organs a greater or less amount of a yellow or brown pigment (hæmosiderin), the "pigment ochre " of Kelsch and Kiener. This pigment is found not only in the capillaries, but also, and in greatest abundance, in the parenchyma cells of the liver, spleen, pancreas, kidneys, as well as in the bone marrow and in the connective tissues. It is not characteristic of malaria, but occurs in all morbid processes in which there is extensive breaking-up of erythrocytes, as in paroxysmal hæmoglobinuria; in pernicious anæmia, in extensive burns, in poisoning by pyrogallic acid, potassium chlorate, arseniate of hydrogen, and many other toxic agents. It has peculiar chemical properties, being equally insoluble in acids, in alkalis, and in alcohol. At first, when freshly deposited, it gives no evidence, under the usual micro-chemical tests, of containing iron; after it has been in the tissues for some time it appears to be altered in character in this respect, and it then gives a ferrous reaction with ammonium sulphide, and with the double cyanide of iron and potassium. Polycholia and hœmoglobinœmia.—— Under ordinary conditions of physiological waste the products of the effete blood- corpuscles are converted into bile pigment, and so got rid of. Up to a certain degree of pathological hæmoglobinæmia the liver can deal in a similar way with free hæmoglobin; so it comes about that, when this substance is free in the blood in unusual abundance the secretion and flow of bile become correspondingly increased. If this flow