Beautiful!

My guess is that the third one is a different variety, one that was in the clump with the blue ones.

Iris often skip a year, especially if they've been moved, so the blue ones will probably return next season (*this* season!), & maybe more of these cream-colored ones will bloom along with them.

*bump*

I got Desert Canyon a couple of years ago, I don't have a photo but mine looked similar, deeper color though than the photo at the site below. Just scroll down for Desert Canyon & see what you think.

Here is a link that might be useful: Desert Canyon

it does look similar, how tall is it though? the site doesn't say. but the standards are only a shade or so lighter than the falls, are yours the same?

I wish I had taken a picture, but the rain ruined the last blooms. The standards on mine are just a bit lighter than the falls. I think mine looks closer to your plant than the one in the photo. I was looking through historic iris & spotted this one, Easter Bonnet
http://www.hips-roots.com/visitors/v-photos/vp-topframe.html

Here is a link that might be useful: Easter Bonnet

i agree, sort of like EASTER BONNET but darker. the colour is really hard to get a fix on though, it's very much shimmery. also my veining around the hafts is more goldish brown then that yellow.