-Pseudo fossil Guilielmites are interpreted, inter alia, as burrows, coprolites, body fossils, concretions, compression cones, and as plant bulbs, seeds, or floats. Regarded initially as fruits, they are described under Calvasia and Carpolithes by Sternberg (1820, 1825), transferred to Cardiocarpum by Bronn (1837), and raised to a new genus by Geinitz (1858).

- Material from Liévin basin (Bolsovian age ) clearly asserts relation between medullosean seeds and pseudo

fossil Guilielmites ,whose in present case could be interpreted like structure indicating compactation or "splach down in muddy sediment " !

-Numerous Alpin material ( Asturian age ) Guilielmites could be regarded mainly as inorganic. Carruthers (1871) interpreted them as fluid casts. Gothan (1909) and Schmidt (1934) suggested they may be gas rise structures.

-For some time they are generally regarded as inorganic structures indicating differential compaction (Elliot 1965) for example elongated shape more 140 millimeters long. Differential compaction may occur about a relatively incompressible object such as a concretion, shell, vertical plant root, or animal burrow. All figures scale bar = 10 millimeters.