Feather and Fan Stitch, or Old Shale
From the Stitch Description: This famous old Shetland pattern, with its deep scallops, is probably familiar to every knitter in one or another of its unnumerable forms. Because it is so extremely simple, it can be varied in dozens of ways. The number of stitches to a repeat can be greater or smaller; the bands of purl across the pattern can be spaced differently, or placed on another row, or broader, or not there at all; the row count can vary, and so on. It is said that in the Shetland Islands no two families of knitters work the pattern alike. But the basic principle of the pattern row is always the same; half decrease, grouped together, and half increases, likewise grouped together.
Location of Stitch: Page 205 from A Treasury of Knitting Patterns.