▁volunte ers : ▁Daniel ▁Sie bert , ▁Se an ▁Thomas ▁ ▁Part ▁three : ▁Hen b ane ▁the ▁w itch es ▁bre w ? ▁ ▁scient ists : ▁Paul ▁De vere ux , ▁author ▁and ▁research er ▁of ▁the ▁cultural ▁importance ▁of ▁hall uc in ogen ic ▁plants ▁Dr ▁D iane ▁Pur k iss , ▁historian ▁and ▁lect urer ▁at ▁the ▁University ▁of ▁Reading ▁Dr ▁Elizabeth ▁William son , ▁from ▁the ▁University ▁of ▁London ' s ▁School ▁of ▁Ph arm acy ▁volunte ers : ▁Paul ▁R ous seau , ▁Jim ▁Bo yd ▁ ▁Part ▁four : ▁The ▁Blue ▁L ily ▁flower ▁power ? ▁ ▁scient ists : ▁Michael ▁Car m ich ael , ▁Eth n ob ot an ist / An th rop ologist ▁Prof . ▁Alan ▁Lloyd , ▁Egypt ologist ▁and ▁chairman ▁of ▁the ▁Egypt ▁Ex pl oration ▁Society ▁Dr ▁Susan ▁D ut y , ▁ph arm ac ologist ▁at ▁King ' s ▁College ▁London ▁volunte ers : ▁Robert ▁Bar nes , ▁Marie ▁McC art ney ▁ ▁The ▁series ▁ended ▁with ▁the ▁investigation ▁of ▁the ▁ps y cho active ▁effects ▁of ▁the ▁ ▁Blue ▁L ily ▁( N ym pha ea ▁ca er ule a ), ▁a ▁sacred ▁plant ▁in ▁ancient ▁Egypt . ▁Michael ▁Car m ich ael ▁suggested ▁that ▁the ▁ps y cho active ▁effects ▁of ▁the ▁blue ▁l ily ▁and ▁other ▁ps y cho active ▁plants ▁established ▁a ▁new ▁foundation ▁for ▁understanding ▁the ▁orig ins ▁of ▁philosophy ▁and ▁religion ▁in ▁ancient ▁Egypt . ▁ ▁Alan ▁Lloyd , ▁the ▁Egypt ologist