Calamites come in a variety of different "form genera." This type, calamites suckowi, is distinguishable from other calamite forms by its prominent, swollen nodes and relatively wide-spaced longitudinal ribs. Calamites cisti, for example, has much smaller nodes and the ribs are typically closer together.
In addition, the distance between successive node lines on a calamites suckowi specimen is typically much wider than the diameter. In other forms, like calamites cisti, the opposite is true or the specimen is just slightly wider than the diameter.
Rock Type: Sandstone; fine-grained
Interval: Coalburg seam
Age: Middle Pennsylvanian Period, approx. 307 million years.
Location: Nicholas County, West Virginia; Ramp Run Surface Mine #1, located about 12 miles north of Summersville, West Virginia. Turn west off route 19 north of Summersville onto Spruce Run Road.