Wow, LariAnn, those are some beauties!
I have noticed that there are some forms of T. venosum that have white markings on the leaves, and others that do not. I have not seen any cultivar names associated with these marked types. Do you know of any?
It also seems there is some variation in flower color and form, yet no named cv.s... seems like there should be.
The only cultivar I have seen is 'Indian Giant' from Brian's Botanicals on eBay.
Also, really enjoy your articles - thanks for your good work and writings.