The bird's nest fungus Cyathusearlei Lloyd produces new diterpenoid metabolites of the cyathin type. Cyathatriol is shown to have structure 1 and has been correlated with cyathin A3. 11,15-O,O-Diacetylcyathatriol (2), 15-O-acetylcyathatriol (3), and 11-O-acetylcyathatriol (4) have also been isolated. The first cyathins containing only two oxygens, cyathin B2 (19) and allocyathin B2 (12), are also described.