ECHINODERMATA—CRINOIDEA. 



507 



26. C. iowensis Owen and Shumard. Mississippic. 



Calyx oblong in outline, owing to the broadly truncated base and 

 straight sides. 



Burlington of Missouri and Iowa. 



2y. C. multibrachiatus Lyon and Casseday. Mississippic. 



Much larger than C. maximus, with numerous, long, slender 

 arms and strong, round stem. 



Keokuk of Indiana. 



28. C. parvibrachiatus Hall. Mississippic. 

 IB small, partly concealed by the column. B very large and 



strongly tumid. Arms short and rapidly tapering. 

 Keokuk of Illinois and Iowa. 



29. C. maxvillensis Whitfield. (Fig. 



1820.) Mississippic. 



Calyx pointed below; sides curving. 

 Maxville of Ohio. 



30. C. stillativus White. Carbonic. 

 Dorsal cup very shallow. Plates very 



convex to angular. 



Carbonic of Missouri and Kansas. 



Fig. 1820. Cyathocrinus 

 maxvillensis, two specimens 

 showing different parts. (After 

 Whitfield. ) 



XIV. Barycrinus Wachsmuth. 

 Differs from Cyathocrinus in its mas 

 sive arms. Ventral sac composed of but few rows of heavy plates 

 longitudinally arranged. Column obtusely five-angled, with very 

 large axial canal. Mississippic. 



31. B. meekianus Shumard. Mississippic. 



Plates massive, convex. IB nearly hidden by the heavy column. 

 R slightly larger than the B. Anals two, the lower very small. 



Chouteau and Burlington of Missouri. 



'^2. B. sculptilis (Hall). Mississippic. 



Calyx basin-shaped, small, with a breadth of slightly over one 

 inch, which is twice the height, truncated at base and expanding 

 rapidly upward. Plates somewhat rugose, very convex medially 

 and deeply excavated at the corners. 



Burlington of Iowa. 



