PLATE XXX. 



¥rom the Neocomian or Lower Greensand. 



Fig. 1 a. Peltastes Wrightii, Desor. Test, natural size. British Museum. (P. 150.) 



b. „ „ Upper surface, showing disc magnified twice. 



c. „ „ Under surface, mouth opening and peristome, 



magnified twice. 



d. „ „ Lateral view of the same, magnified twice. 



e. „ „ Upper portion of an inter-ambulacral and am bu- 



lacral area, magnified four times. 



/. ,, „ Inter-ambulacral tubercle, magnified four times. 



Fig. 2. „ „ Abnormal disc, suranal absent, do. twice. 



