providing a growing surface in {TAIL ~ said water} to which said algal spores form {HEAD ~ an attachment} 
providing a growing surface in { TAIL ~ said water } to which said algal spores form { HEAD ~ an attachment }
OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD