a sucky one hahaha kidding, i dont know i am also trying to find this answer they probably of a good done though
An open circulatory system.
A closed circulatory system
Closed Circulatory system
They have a closed circulatory system.
closed circulatory system
Closed circulatory system I believe.
They have a closed circulatory system.
closed circulatory system.
closed circulatory system.
earthworms have a closed circulatory system
earthworms have a closed circulatory system
Closed (I think. All vertebrates I know of have a closed system)