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Black Hills Institute of Geological Research, Inc.: Crinoids
Site provides a detailed overview of crinoids, more commonly referred to as "sea lilies" and "feather stars." Content includes a focus on the animal's endoskeleton, feeding, commensalism, habitat, value, forms, and more. Also has great...
Tree of Life Project
The Tree of Life Web Project: Crinoidea
This site from the University of Arizona provides a very thorough information on chrinoidea, including diagrams and pictures.
Other
Wet Web Media: Crinoids
A great site on everything you need to know about crinoids, including species, types, environmental conditions, ecosystems, and pictures.