In one embodiment, the fourchette extends to the edge of {HEAD ~ an opening} formed by {TAIL ~ the fourchette} and the anterior and posterior portion 
formed by
In one embodiment , the fourchette extends to the edge of { HEAD ~ an opening } formed by { TAIL ~ the fourchette } and the anterior and posterior portion
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH