Weight: 13.3 Ounces
Dimensions: 6.5 Inches Long, 2.3 Inches Wide, & 0.8 Inches Thick
The item pictured is the one you will receive.
The Trackways date to the Ordovician (450 million years) Period.
Ichnofossil or trace fossil is an impression left by an animal. In this case, they are the impressions left behind by a trilobite as it trekked across the muddy ocean bottom. There are three kinds of ichnofossils created by trilobites. An impression of the body of the bug laying in the mud and tracks created by waking slowing and track created when the bug is up and zipping along the ocean bottom. The three types of traces can morph into one another, and the transitions are related to whether the animal is stationary or moving, the speed of movement, and whether the trilobite is partially buried or fully emerged in the mud.
When a trilobite is resting, partially buried in the mud of the benthos, it leaves a bi-lobed impression called a Rusophycus, that is sometimes marked by parallel marks that correspond to its legs. It looks like a very fat, irregularly shaped almond stuck in the mud.
Cruziana are tracks showing rather clearly defined edge furrows, probably created by a trilobite moving, partially buried, through the mud. The widest part of the shell leaves the parallel outer furrows, while the leg movements create the chevron-shaped marks in the center of the track.
Finally, when a trilobite is walking or striding freely upon the surface, it leaves paired leg marks called Diplichnites which can be reduced to rather widely-spaced impressions when the animal is striding at full speed across the substrate. It basically looks like mini tank tracks cruising through the mud.