{TAIL ~ a second opening} in surface portions thereof longitudinally spaced from {HEAD ~ said first opening} and toward said free extremity, 
{ TAIL ~ a second opening } in surface portions thereof longitudinally spaced from { HEAD ~ said first opening } and toward said free extremity ,
TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH