Morphology, histochemistry and the biological significance of the lymphatic system of the trematodeOrthocoeliumscoliocoelium

Abstract

ABSTRACTThe gross morphology and histological and cytological architecture of the lymph system ofOrthocoelium scoliocoeliumwere studied. Each main vessel, near the intestinal bifurcation forms a spindle-shaped sinus. Lymphocytes, similar to the primitive blood cells, have been seen to form aggregates in certain regions of the lymph system. In addition, detailed histochemical observations were made on the localization and distribution pattern of various phosphatases, esterases and dehydrogenases. It is suggested that the lymph system, in addition to the functions already known, may also selectively reabsorb certain important outgoing higher fatty acids from the excretory system. Furthermore, the lymphocytes may also be involved in the defence mechanism of the worm. The nature and function of fine granules in the lymph remain speculative.