Be aware that sometimes you can have a double daylily which will also exhibit some degree of polymerous behavior. 'Alternate Behavior' is a Stamile double daylily which will sometimes (at most 10% in my garden) produce polymerous segments, in addition to the double behavior.
The opposite is also true - a poly bloom can produce petaloids created from the stamens. Last summer I had maiden bloom on a seedling of uncertain ancestry (though I believe that 'Hip to be Square' figured somewhere in the background). Four of the five blooms showed extra tepals in one configuration or another, and at least one of the blooms also had petaloids (doubling). (I will spare you the horror of pictures. Thus far this season it has bloomed all of one poly bloom
; I am waiting to see what transpires with the rebloom scape.)
