the body of eathworm can be distingushed into dorsal ventral sides due to the prsence of certain pecuioler feature in it like
(i) the dorsal surface is darker then ventral surface because it is maked by a darak median mid dorsal line along the longitudinal axis of body this is due it is marked by a sark vessel seen through interument ,
(ii) the ventral surface genotal openings (pores ) both male and female
(iii) GEnital papilla is located on ventral surface and help in copulatior.
