The Phyla Annelida mostly consists of segmented worms. Annelids have bilateral symmetry. Annelids only use sexual reproduction. Annelids have a segmented body meaning segments divided by a septum.  The digestive system of Annelids have an unsegmented gut that runs from the mouth to the middle of the body.  The nervous system has a single or double nerve cord that goes throughout the body. I find it interesting that an organism can be separated into parts and be able to function at the same time.

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Leech

Leeches have a coelom unlike some animals. Leeches also have two "suckers" on their body used for sucking blood.

Echiura

Echiura is a kind of Annelid that live in shallow waters such as lakes and ponds.  Yet there are also a few Echiura's that live in deep waters.

Clitellata

Clitellata's are characterized by their "clitellum", that forms a reproductive protective layer.