Donald,
I've seen the common name for Rhoeos as 'Moses in the Cradle' (because the shape of their blooms), but not for T. pallida.
Not my image, but this is where I think the reference comes from (for Rhoeo).
The only cultivar name I know of for T. pallida is the purple one, it is known as 'Purple Heart. But, I don't know of a "common name" for them as a whole. There's T. zebrina, 'Wandering Jew,' but that's a different species.
Planto