This is a canvaswork filling stitch consisting of diagonally offset ovals. It is similar to condensed Scotch stitch, although the motifs are slightly elongated as the stitches are worked over two, three and four intersections in sequence (condensed Scotch is over one, two and three intersections).
... and finally over three and two intersections to complete a diagonal oval shape.
Work back up repeating the stitches. The shapes should fit neatly together with the small stitch touching the longest stitch of the previous row ...
Structure of stitch
Mrs Archibald Christie, Samplers and Stitches (1921) , p.92
Mary Thomas’s Dictionary of Embroidery Stitches (1934) , p.74–5