The apparatus 13, wherein said aperture is of {HEAD ~ a width} to permit {TAIL ~ the head} of said animal, but not the shoulder through 
to permit
The apparatus 13 , wherein said aperture is of { HEAD ~ a width } to permit { TAIL ~ the head } of said animal , but not the shoulder through
OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH