Fig. 1

Representative examples of members of the Parvclass Disparida: a lateral view of crown and proximal column of Ectenocrinus simplex (Hall 1847); OSU 54458; b lateral view of crown and proximal column of Parapisocrinus quinquelobus (Bather 1893); from Springer (1926a); c lateral view of crown and proximal column of Catillocrinus tennesseeae Shumard (1865); from Springer (1923); d lateral view of crown and proximal planispirally coiled column of Myelodactylus extensus extensus Springer (1926a); from Springer (1926b); e lateral view of aboral cup of Zophocrinus howardi Miller (1891) from Springer (1926a); f lateral view of crown and proximal column of the calceocrinid Halysiocrinus tunicatus (Hall 1860); from Springer (1926a). Scale bars 5 mm