To the left is a picture of a 
relatively complete crinoid from 
Morrocco.
#1 are stems
#2 is the calyx
#3 are the arms

Top right is a calyx with arms 
from Nashville TN
 
 
 
 

Bottom right is a bottom view 
of the calyx of the same crinoid (different individual) showing 
the stem attachment
 



Information provided by: http://inst.santafe.cc.fl.us