PLATE XXVIII. 



Prom the Upper White Chalk. 



Fig. ] a. Cyphosoma spatuliferum, Forbes. Test, natural size. British Museum 



(P. 141.) 



1 b. 



„ Upper surface of do., raagnified tM'ice. 



1 c. 



„ Under surface of do., do. do. 



1 d. 



„ Lateral view of do., do. do. 



1 e. 



„ Inter-ambulacral plates, do. six times. 



If- 



„ Ambulacrum entire, do. do. 



1^- 



„ Inter-ambulacral plates, do. do. 



1 h. 



„ Lower portion of an ambulacrum, mag- 



nified six times. 



