Aristolochia ringens is called the 'Pelican Vine'. Do a google.com search for the botanical name and I am sure you will find the information you seek.

I purchased the pelican vine from ebay auction in February 2004. I bought two gallon containers and it has been one of my favorite plants. They grew in containers for 2 years but did not come back in 2006. I am currently trying to locate either plants or seeds. It has 2" round leaves and makes seeds that can be easily sown. the seed pod is star shaped and about 2 1/2" long and opens in a peculiar way. It grows best in full sun to part sun, blooms in spring, summer, and fall and does well in Zones 8-11. Plant in well drained soil.It is a host plant for pipevine swalowtail butterfly. The formal name is Aristolochia Grandiflora. Please let me know if anyone has seeds. There is no listing on ebay at present.