Shell stitch
- Fan stitch
- Scallop stitch

This canvaswork stitch consists of vertical bundles of straight stitches pulled together in the centre with a couching stitch and then embellished with loops threaded through the couching stitches. A backstitch is worked between rows.
It is sometimes known as fan stitch, not to be confused with another canvaswork stitch called fan stitch.
Method
This decorative stitch is worked in several stages. First the vertical bars are put in across six horizontal threads of canvas. Each stitch has five of these bars.
The last on each group and the first of the next group share the holes of the canvas.
Work these across the row.
Next, tie each group together with a horizontal stitch over the two central threads of canvas. You will need to angle the needle out from the stitches and tuck it back round each group.
Now the groups are linked together with one continuous surface thread. Starting somewhere to the left of the groups, thread the needle under the first holding stitch from top to bottom.
Take the needle across to the second group and thread it through this group from from bottom to top.
Again take it through the first and second holding stitches in the same direction. Do not pull the yarn too tight.
Take the needle across to the third holding stitch and through from the top to bottom, then back to the second holding stitch and through from the bottom to top and finally to the third holding stitch and through from top to bottom.
Continue across the row linking the groups.
To cover up any bare canvas that might show when finished, work a back stitch across two threads of the canvas between each row where they meet.

Embroidery Techniques
References
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Mary Thomas, Jan Eaton, Mary Thomas’s Dictionary of Embroidery Stitches (Revised Edition) (1989) , p.163
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Jennifer Campbell, Ann-Marie Bakewell, Guide to Embroidery Stitches (2004) , p.217