The adult worms of Schistosoma mansoni live in the veins of the portal system, mainly in the radicles of the inferior mesenteric vein. The eggs are deposited in the venules of the submucosa in the large bowel and escape through the mucosa into the intestinal lumen, mixing with the feces. However, many eggs do not reach the intestinal lumen but are retained in the intestinal wall itself or may spread to many organs or tissues not related to the portal venous system, i.e., lungs, central nervous system, heart, kidneys, thyroid, etc. (Faust, 1948; Maciel et al., 1954; Lichtenberg, 1955). The eggs reach the lungs through the hemorrhoidal plexus, a communication between the portal and systemic venous systems (Mainzer, 1951). The frequent liver cirrhosis in schistosomiasis widens that communication. The routes of dissemination to other organs are not known and many theories have been adduced.