Jonathan, I think the best way is having pictures of each but otherwise, narcissiflora has straighter tepals while Festalis has longer, more curved tepals. Festalis is pretty common, while true narcissiflora is very rare. Other than Festalis, one usually sees only "Advance" in cultivation. Ismene longipetala has a somewhat curved cup. Ismene amancaes and its hybrids are yellow or yellowish. Jim At 01:45 PM 3/13/2014, you wrote: Jim, how does one distinguish between I.narcissiflora and I. 'Festalis'? > > >Thanks, > > >Jonathan Lubar >Alachua FL z8b > > _______________________________________________ -- James Shields firstname.lastname@example.org P.O. Box 92 Westfield, IN 46074 U.S.A.