The front seating area is defined by a generally semi elliptical front perimeter surface while {HEAD ~ the rear seating area} is defined by {TAIL ~ a different, generally semi elliptical rear perimeter surface} 
is defined by
The front seating area is defined by a generally semi elliptical front perimeter surface while { HEAD ~ the rear seating area } is defined by { TAIL ~ a different , generally semi elliptical rear perimeter surface }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL