Where is the glandular swelling on the earthworm found?

The glandular swelling is found on the back of the earthworm and is called C.litellum.
An earthworm is tube shaped and it belongs to the Annelida phylum. It is usually found in the soil, where it contribute to the level of fertility of the soil by feeding on the dead organic matter and by aerating the soil. Earthworms lack internal skeletons and they are hermaphrodites. 

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