A wall is formed in {HEAD ~ the bottom ply} which defines {TAIL ~ a well} into which a fragrance sample is deposited 
defines
A wall is formed in { HEAD ~ the bottom ply } which defines { TAIL ~ a well } into which a fragrance sample is deposited
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH