Cretaceous fossil
This image is from a fossil in limestone from central Montana. It appears as rib like growth rings??, on what is assumed to be a mollusk of some sort. The sample is about 12 inches top to bottom which makes for a fairly large mollusk. The backside is simply sandy mud stone with one or two smaller smooth mollusks embedded about the size of the smooth casting circle on the left. I am totally at a loss for identification of what would leave this pattern of relief on the rock. I would appreciate
Well done!
Just to complete: Inoceramus (Volviceramus) (aff.?) involutus Sowerby, 1826 -------------------------------------------------------------------------- Inoceramus involutus Wolleman,1902 Volviceramus involutus Woods,1912 Die Lowenberger Kreide und ihre Fauna - Hans Scupin,1912-1913 - Pl.12, Fig.3
Molluscan Fossil Record from the Northeastern Part of the Upper Cretaceous Seaway,Western Interior - William A. Cobban, page7
"Volvicer
