416 REPORT OF THE HARVARD AFRICAN EXPEDITION 
that the Babesia which he discovered is readily transmissible to the domestic 
eat by means of blood inoculation. 
HELMINTHIC INFECTIONS OF MONKEYS 
A number of other parasitic infections were observed in monkeys. In a red 
Colobus (rufomitratus) monkey in the Ituri Forest, a severe infection of the liver 
with trematodes was observed. At the necropsy the liver contained a number 
of small whitish areas from 3 to 4mm. in length and one infarct 4 mm. in diameter, 
irregular in outline and almost quadrilateral in shape. Small trematodes, ap- 
proximately 3 to 4mm. in length, were found in many parts of the liver particu- 
larly in the whitish areas or in the greatly distended bile ducts from which many 
of them could be easily expressed. The spleen was not particularly enlarged 
but was very dark in color. Examination of the blood films of this animal later 
revealed a malarial plasmodium. Slices of the liver were placed in Zenker’s 
solution and the trematodes removed from the liver were also hardened in Zen- 
ker’s solution and in formalin. A small number of nematodes (Trichuris trich- 
jura) were also found in the caecum and large intestine of this animal and placed 
in formalin (see page 478). Histological study of sections of the monkey’s liver 
upon our return showed that many of the bile ducts were prominent and greatly 
distended in size and often contained sections of the trematodes lying within 
them (No. 350). Many of the parasites in the tissues contained ova. The 
epithelium lining the ducts in such cases was compressed, degenerated or de- 
stroyed. There was frequently some infiltration of round cells and leucocytes 
about the walls of the ducts. In some areas the connective tissue surrounding 
the bile ducts showed evidence of proliferation and distinct thickening and in 
places this tissue was also infiltrated with round cells. The surrounding hepatic 
tissue was compressed by this new growth and the liver cells showed cloudy 
swelling, and in other areas moderate fatty degeneration. About some of the 
parasites which had apparently died and were themselves degenerating, there 
was very marked necrosis of the liver and very extensive infiltration of the tissue 
with polymorphonuclear and endothelial leucocytes, more or less surrounded by 
areas of round cell infiltration (No. 351). In some areas the liver showed evi- 
dences of chronic passive congestion with extravasation of red blood corpuscles, 
the liver cells being pushed apart and the capillaries widened. There was also 
evidence of proliferation of the epithelium of some of the bile ducts, but no adeno- 
matous growth was anywhere observed. The endothelial cells about some of the 
blood vessels were proliferated and there was likewise evidence of a fine cirrhosis 
in parts of the liver. In still other areas there were numerous newly-formed bile 
canaliculi. In the regions of more normal liver tissue, away from the sections of 
the trematodes, miliary areas composed of round cells were not infrequently 
present. These areas are somewhat similar to those observed in the liver of 
human cases of diphtheria. They especially suggest that the parasite is able 
not only to produce pathological changes mechanically by its presence in the 
bile ducts and tissues, particularly through pressure, but also through some 
toxic secretion. The liver of this monkey showed evidences of very extensive 
