File:Proboscidea parviflora - double claw - seeds inside pod.jpg

English: Proboscidea parviflora - Here shown a dried, opened double claw seed pod showing how the first layers of black seeds fit together. Behind them on each side, tough ovary walls protect a second layer of seeds. The seed pod form allows it to slowly split symmetrically to open to drop only a couple of seeds at a time, reducing chances for overcrowding of sprouts in any one spot. The ovary walls hold the remaining seeds much longer before they degrade enough to release the seeds inside them. A very important traditional indigenous edible and useful plant of the southwest United States. When green the distinctive curve of this fruit earned the name 'unicorn' plant, but when dry the fruits split along the spine to form a double hook, known as the 'double claw'. The dried seeds are edible and highly nutritious, and can be eaten dry, crushed for oil or ground into flour. The splints from the longest, dried curved 'hooks' are collected for south-western U.S. traditional Native basket-making. Roughly 25 - 30 seeds in an average seed pod. Grid size - centimeter with millimeter. Seeds shown are 1 centimeter in length.