A singular plant, of the nature of the ferns, but not like any of them in form. The root is fibrous. From this the leaves rise in great numbers together, each being a distinct and separate plant; they are narrow, and five inches long, deeply indented on each side, but very irregularly, and covered on the under part with small seeds. When they first grow from the root, they are folded inward, so that only the under part appears; and they have a very peculiar aspect, more like some insect than the leaf of a plant. It grows on old walls, and is green all the winter, but it has most virtue in spring.
The whole plant is used. It is best given in infusion, and must be continued for some time; it opens all obstructions of the liver and spleen, and is excellent in disorders arising from that cause. They say the powder of the dried leaves cures the ricket, but this wants proof.