I find these fossils all the time along the shores of Lake Michigan. These crinoid fossils are commonly referred to as “sea lilies“ because of their colorful flower like appearance when they were living beings, but were a type of animal. They possessed long branching arms that sat atop of a single stem reaching as high as two meters in length. They attached themselves to the sea floor or on rocks or even sunken wood. A spawning of their offspring from these bottom bound creatures may have looked like thousands of dandelion seeds blown by the wind.
Their fossils are often found broken up into individual “cheerio” shaped sections. Each circular section was stacked one over the other when they were alive which formed their entire structure. The Native Americans used their fragmented fossilized sections to make necklaces and so another common name for them some people use is Indian Bead.