in this vessel it is included, not only in the leucocytes, but also in certain large white cells identical with those occurring in the spleen, and, doubtless, of splenic origin also. Similar cells may be found in the capillaries of the liver, rarely, however, in the blood beyond this organ; that is to say, they are filtered out by the liver from the blood carried to it by the splenic vein. An additional reason for the abundance of hæmozoin in the splenic vein is, that not only is the spleen the physiological destination of many of the hærnozoin-laden leucocytes and effete parasite-infested corpuscles, but it is likewise a favourite nursery for the parasite. In fact, the parasite is present in this organ in greater profusion than elsewhere. Hence it is that the splenic vein, coming direct from a rich breeding- and dumping-ground, contains a large number of hæmozoin-laden leucocytes.
Extravascular pigment.——In the early stages of malarial disease, except in the case of the spleen and the bone marrow, pigment is entirely confined to the lumen of the vessels and to their endothelium. But if we examine tissues from a case which has died at a late period of the disease, the pigment may then be found, not only in the endothelium, but also in the walls of the vessels, and even in the perivascular lymph spaces, whence, it may be inferred, it is subsequently carried to the lymphatic glands to be finally dealt with and broken up. As encouraging this view about the ultimate fate of the malaria pigment, Kelsch has pointed out the significant fact that the lymphatic glands in the hilum of the liver are always markedly pigmented in old-standing malarials; a fact evidently referable to the disposal of the large quantities of hæmozoin which, as we have seen, the liver filters out, more especially from the splenic portion of the portal stream.
These facts explain malarial pigmentation and oligocythœmia.—— The facts just mentioned explain the origin and nature of malarial pigmentation, and also, in part at least, the oligocythæmia of the malarial state, which, as pointed out, is only partially accounted for by the destruction of corpuscles by the
