The discs may include perimeters having ovular or elliptical shapes that cooperate with {TAIL ~ a cylindrical interior wall} of the housing to cut {HEAD ~ tissue} specimens 
The discs may include perimeters having ovular or elliptical shapes that cooperate with { TAIL ~ a cylindrical interior wall } of the housing to cut { HEAD ~ tissue } specimens
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH