That certainly matches the caterpillar of Vanessa virginiensis Rick! Look at the photo on the right column ..
http://www.butterfliesandmoths...
I have two Mullein moth cats on Verbascum thapsis, they live around the flower buds as they open but don't seem to be eating flowers. Sometimes I see them, sometimes I don't, I don't know where they disappear to as they are quite big.
