There's a beautiful specimen at the Subaru sponsored building off the Hwy near UH Hilo. I wish I could be more specific. But here's a shot of the flower in the graden of native flowers they have.
http://www.pbase.com/selvin/image/73080134 and a specimen of the yellow can be found on Kumukoa near Mohouli at a private residence.
http://www.pbase.com/selvin/image/37921039 Aloha and good luck.
