and indicate {HEAD ~ the position} directed by the contents of the IMA counter to represent {TAIL ~ the position} of the present cursor 
and indicate { HEAD ~ the position } directed by the contents of the IMA counter to represent { TAIL ~ the position } of the present cursor
OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH