Taken from Sockupied: "A cataphyll is a specialized leaf whose main job is not photosynthesis. The leaves on this sock trail down the leg then split in two; half continue down the heel while the others wind across the foot."
This pattern is from Sockupied, pg 71 - Cataphyll Sock.
Size US 1 double point needles, US 1 - 32" circular needles (or size needed to obtain gauge), stitch markers, and a tapestry needle are required but not included.