Aargh! Just had a long post all typed out, went back to look more closely at the photo on the camera of my phone and "poof" - the post disappeared. No warning no nothing. Just gone. I will get better at this - in time.
Anyway... Here are the two different color forms of Iris foetidissima, the Gladwyn iris, that are in our garden. The purple blue form is the standard species. The light yellow is 'Citrina'. Note the beautiful and very different coloring of each. The blue form is only bluish on the netted falls. In the center of the flower the colors are bronze and burnt orange over an ivory background. In Citrina, the netted falls are ivory edged in light yellow, with purple veining, while the central flower parts are dusky purple infused over light yellow. Both flower forms are quite lovely.
Foliage doesn't seem to be much different - long strappy dark green leaves 18"-2ft long. And the clumps are evergreen. The Citrina seems to grow a bit taller than the blue form. There is also a variegated form that I will showcase when it flowers.