Stigmaria is the name of the root bearers of
Lepidodendron- as well as of Sigillaria trees. They
were growing widely and superficially,
forking dichotomously and could in this manner take up a large surface. This
adaptation made it possible for the trees to stay
upright in a swampy environment. When the rootlets had disappeared, circular
scars (stigmata) remained.
Height of the photo 8 cm.