In this article we will discuss about Nephridium of Annelida:- 1. Definition of Nephridium 2. Research Work on Excretory System 3. Classification of Nephridia 4. Physiology 5. Functions. Definition of Nephridium: An excretory tubule which opens to the exterior through the nephridiopore and the inner end of the tubule is blind (associated with terminal cells […]