Passively filled

Take me to the ichnology start page!

Take me back to the beginning of the determination key!

Take me to the alphabetical list of ichnogenera!

Is the (sub)horizontal, unbranched burrow with a cylindrical cross section or a ridge-like appearance and a passive filling lined or does it have a mantle? Please, choose accordingly:

  1. With lining/mantle
  2. Without lining/mantle

Take me to the ichnology start page!

Take me back to the beginning of the determination key!

Take me to the alphabetical list of ichnogenera!

[Passively filled]