PLATE XXII. 



EcUnocyphus from the Grey Chalk. 



Fig. 1 a. 



1 b. 

 Y\o. 2 a. 



2 h. 

 2 c. 

 '2d. 



EcHiNOCYPHUs ])iFFiuiLis, Agassiz. Test, natural size. British Museum. 

 (P. 116.) 



Ambulacral and inter-ambulacral plates, magnified four diameters, do. Do. 



EcHiNOCYPHUs DiFFiciLis. Upper surfacc, magnified three diameters. The Rev. 



T. Wiltshire, F.G.S. 

 „ „ Under surface, do. do. Do. 



„ Lateral view, do. do. Do. 



,, Ambulacral and inter-ambulacral plates, magnified 



six times. 



Fis. 3 a. EcHiNOCYPHus mespilia 



natural 



(P. 119.) 



8 b. 



3 e. 



3 d. 



3 e. 



Fig. 4. 



Fig. .5 a. 



5 b. 



5 c. 



5 d. 



echinocyphus difficilis 

 Cyphosoma Konigi 



Woodward, sp. Test, 

 British Museum. 



Upper surface, magnified three diameters. 

 Under surface, do. do. 

 Lateral view, do. do. 

 Ambulacral and inter-ambulacral plates, 

 magnified eight diameters. 

 Apical disc, magnified four times. 

 Mantell. Young test, natural size. British Museum. 

 (P. 131.) 



Under surface, do. Do. 

 Lateral view, do. Do. 

 Upper third of ambulacrum, magnified four 

 times. 



