The cover defines a dispensing orifice and defines an edge for severing at least part of the membrane as {HEAD ~ the cover} is moved from {TAIL ~ the outer position} to the inwardly displaced position 
is moved from
The cover defines a dispensing orifice and defines an edge for severing at least part of the membrane as { HEAD ~ the cover } is moved from { TAIL ~ the outer position } to the inwardly displaced position
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH