Reversed fly stitch
This stitch consists of two interlocking fly stitches: one is stitched as a V or Y and the second is rotated 180 degrees and stitched over the top. This results in an intricate isolated stitch which can be used as an open filling or joined into lines.
Bring your needle up at the left end of the bottom guide line and take it down a short distance to the right.
Leave a loop on the surface and bring up your needle inside it to form an upside down V shape. Tighten the loop against your needle.
Bring your needle up on the top guide line, immediately above the start of your first stitch. Take it down on the same guide line immediately above the end of your first stitch.
Leave a loop on the surface and bring up your needle inside it to form a V shape. Tighten the loop against your needle.
Take your needle down immediately outside of the V to anchor your stitch. This completes your first reversed fly stitch.
Bring your needle up on the bottom guide line, slightly to the right of your previous stitch.
Structure of stitch
Mary Thomas, Jan Eaton, Mary Thomas’s Dictionary of Embroidery Stitches (Revised Edition) (1989) , p.76
Sarah Whittle, The Needlecraft Stitch Directory (2012)