As a kid I would accompany my older brother on fossil collecting trips. Most any hill in Kansas with a road cut-out would have exposed limestone. Limestone is made from accumulated sea creatures and plants. I found a variety of crinoids. I only found the harder stem pieces. The crinoid is an animal which consist of a stem which anchors itself to the ocean floor. At the end of the stem is a cup-like calyx which contains the mouth and digestive system. Attached to the calyx are arms which sway to and fro with the ocean currents to gather food. The number of arms come in multiples of five. Crinoids date back 500 millions years. Due to the fact that they look like flowers, they are commonly referred to as sea lilies. The starfish is a descendant of the crinoids.
There is a particularly spectacular crinoid known as an unitacrinus. This version was stemless and had 10 arms. It was not rooted to the sea floor. It floated around "arm-in-arm" with other unitacrinus to form a large colony of sea lilies. They were common in the Cretaceous Period, roughly 75 million years ago. The Niobrara Chalk of western Kansas, particularly of Gove County is where good examples have been found.
The Sternberg Museum of Hays, Kansas is named for the Sternberg family of famous fossil hunters. George F. Sternberg was born here in Lawrence. His many fossil finds can be seen at the Sternberg, the University of Kansas Museum of Natural History, the Fick Fossil Museum, British Museum, in London, Victorian Memorial Museum, Ottawa, Canada, the Smithsonian Museum of Natural History in Washington, DC and many others.
The Sternberg is famous for its famous "fish within a fish" fossil, a giant 14 foot long fish which ate a 6 foot long fish and died, fossilized intact. It is on display and truly is spectacular, but their fossil "mural" of unitacrinus sea lilies is stunningly beautiful to gaze at and is equally worthy of your attention. If you are driving through our state on I-70, you should plan to have a rest stop at the Sternberg.
As a kid I would accompany my older brother on fossil collecting trips. Most any hill in Kansas with a road cut-out would have exposed limestone. Limestone is made from accumulated sea creatures and plants. I found a variety of crinoids. I only found the harder stem pieces. The crinoid is an animal which consist of a stem which anchors itself to the ocean floor. At the end of the stem is a cup-like calyx which contains the mouth and digestive system. Attached to the calyx are arms which sway to and fro with the ocean currents to gather food. The number of arms come in multiples of five. Crinoids date back 500 millions years. Due to the fact that they look like flowers, they are commonly referred to as sea lilies. The starfish is a descendant of the crinoids. 
