Earthworm

In cockroach, the blood vascular system is of open type, i.e.9 the blood does not flow in the vessels or capillaries, but moves through the internal open spaces and comes in direct contact with the body organs. The system comprises of haemolymph ( = blood), haemocoel (body cavity filled with haemolymph) and heart. Snail is a mollusc. It also has an open type of blood vascular system. It includes dorsal heart, arteries that open into sinuses (spaces) and veins.