In the Le Grand quarries there is an unusual occurrence of multicolored crinoids. Some of these crinoids are almost black, some are almost white, some are dark brown, some are light brown and some are cream colored. Each species is found always to have the same color. One familiar with the fossils can classify them accurately by the color. Platycrinus symmetricus is a dark brown. Diochrinus inornatus is a chocolate brown and Rhodocrinus kirbyi is almost black. Most of the inadunate species are white. One species with unusual coloring is Rhodocrinus watersianus with a mottled brown calyx and light colored arems.
Proceedings of the Iowa Academy of Science
©1941 Iowa Academy of Science, Inc.
Beane, B. H.
"Crinoids Varied in Color at Le Grand, Iowa (Abstract),"
Proceedings of the Iowa Academy of Science, 48(1), 295-295.
Available at: https://scholarworks.uni.edu/pias/vol48/iss1/68