PLATE LXXIl. 



HoLASTER L^vis, Be Luc. 



From the Upper Greensand. 



Fig. 1 a. Under surface, natural size. My collection. (P. 310.) 



b. Upper do. do. 



c. Lateral view do. 



d. Posterior border and periprocte. 



e. Anterior do. and anteal sulcus. 



/. Primary tubercles and granules, magnified. 



HoLASTER LiEvis vur. PLANUS, Muntell. 

 From the Lower Chalk. 



Fig. 2 a. Under surface, natural size. My collection. (P. 317.) 



b. Upper do. do. 



c. Lateral view do. 



d. Anterior border and anteal sulcus. 



e. Posterior do. and periprocte. 

 /. Poriferous zones, magnified. 



