The first quilt is what a DWR would look like with just the block that you have posted. (I intentionally left a space inbetween the blocks.)
The second quilt shows the additional block needed to complete the quilt to duplicate the one you have shown. This block can be made rectangular, so that there isn't as much extra blank space. It can also be made with just the melon pieces, so that it finishes with a scalloped edge