http://www.imamuseum.org/art/collections/artwork/quilt-sunflower-marie-d-webster. Marie Webster's quilt has some spider web shaped quilting.
If you look at the Marie Webster design, you can see that mine is different. In particular, look at the stems. After some searching, I found a quilt similar to mine on The Quilt Index. Sunflower Quilt
It appears that my quilt is based upon a Mountain Mist pattern and was made sometime between 1930 and 1949. Here is another similar quilt. Sunflower Quilt
You'll note that my quilt does not have a border as do the two shown from The Quilt Index.
Here are some additional photos of my quilt. The quilting is in the designs of sunflowers and leaves.