It's not caused by a bug! I just read the email I received back from the Ag. Dept. and they told me that it was a virus that did all the neat designs. Aphids carry it from one plant to another. It called: Papaya ringspot virus. Go figure. Even though it's a virus I love the patterns one can get on the outside of the watermelon. We plan on looking forward to new patterns on our melons next year.