Distinguish between the Prostomium and peristomium
The prostomium is the pinnacle element that's fleshy and segmented and the periosteum is the primary section of the frame of annelid. - The distinction among the prostomium and peristomium is that, the prostomium is the the front of the mouth determined in annelid at the same time as peristomium is the encompassing of the mouth opening.
