There are many types of Blood Worms, but the one pictured is Glycera americana, the origin of the name means it is from North American, and is commonly used as a fishing worm. The worm itself is a poor swimmer, but furrows itself into the ground. Depending on the conditions that it is living in will determine its length. It is also worth noting that this is regarded as marine life, thus meaning that lives in water. The circulatory system of the Blood Worm is known as a closed circulatory system meaning that it has blood vessels (minor ones). This worm also has multiple hearts (around 5) to pump the blood throughout its body.