Pearl stitch is a looped stitch which, when worked closely together, resembles a string of pearls. It is formed by consecutive loops, each of which are anchored by a short, slanted stitch.
Pearl stitch is a characteristic stitch in Wallachian embroidery, a technique from Wallachia in what is now Romania. Examples of Wallachian embroidery were displayed in the 1851 Great Exhibition in London.
Structure of stitch
Mrs Archibald Christie, Samplers and Stitches (1921) , p.36-37