Diagnosis. Biogenic sculpture consisting of a system of canals radiating from a nearly central origin, which is etched into the surface of a hard substrate. The canals subdivide, usually dichotomously, into finer branches, but do not taper strongly towards their distal ends. They locally join up to form a net-like pattern. The angles at points of bifurcation and intersection are usually widened and rounded.

Branched, network, etching trace.