{TAIL ~ a tubular body} which defines said passage, the tubular body having an opening on {HEAD ~ the distal end} therethrough 
{ TAIL ~ a tubular body } which defines said passage , the tubular body having an opening on { HEAD ~ the distal end } therethrough
TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH