first fossil post need help

[BOATY]

This is my very first post here. Just wondering if someone had an idea on this. Found it near a lake in Iowa

 

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[garren]

This looks a lot like what you have...
If you scroll down to page 205, ignoring the blank pages, it describes the image

http://biodiversitylibrary.org/page/1523621

 

[gunsil]

Looks like a part of a crinoid to me. Very cool!!