I understand there are over 350 species in the Cissus genus. It will be difficult to ID it but as I understand there are two types of C. quadrangularis. One with corky edges on the stems, on has smooth edges which would be similar to yours. I've also seen some with truly round leaves where yours appear to be almost heart shaped. That may be one plant to just 'enjoy' and not wonder.
I've also read that only one is specifically medicinal but I agree with Vickie on the medicinal qualities of plants. I am one that believes every plant was put on this earth for a reason. We just don't always know why...
Now, even though the greenhouse is full, there is one more Cissus that I lust after and the search is part of the fun.
In the meantime, I've found some new plant sites to lust through.
