Surface darning stitch
This stitch is a form of darning with minimal contact with the fabric. A layer of slightly-spaced laid work is stitched, and then another layer at 90 degrees is woven in and out of the laid work. Both layers of stitching only penetrate the fabric at the start and end of each row.
N.B. the term surface darning can sometimes be used for various forms of couching.
Structure of stitch
Mary Thomas, Mary Thomas’s Dictionary of Embroidery Stitches (1934) , p.114