This species was much admired in the mid-nineteenth century, but not every artist got it right. It’s possible that most representations were created from viewing dried material, or from verbal descriptions. It’s important to note that the species is likely quite variable, and not all individuals have the clear green corolla limb that we see in cultivated plants now.
A better representation of the species might be this print from Linden in 1870, which conforms nicely to the actual live plant shown here.
