From book’s pattern description:

"An illustration of a petticoat with a scalloped hem in a late-19th-century knitting book inspired Veronik Avery to design these feminine socks.  The diagonal stitch-patterning is pretty and unusual and holds the socks in place just as well as the more typical vertical ribbing.  Veronik has included directions for working these socks in the round using either five double-pointed needles or two circular needles."