do you know the name of this flower?

I'm dying to know. My apologies for the bad photo. I couldn't keep my hand steady enough for my cell phone. Apparently, it also has a hard time with close ups.



We were at the Houston Children's Museum on Saturday and had a wonderful time even though it was packed (everyone escaping the heat?). When we went to the outer area of the museum, these flowers just jumped out at me. They look amazing in person and it seems that they grow in vine fashion.

EDIT - Gosh you're all so fast! So, it's a passion flower. Thanks everyone!