PLATE XXII. 



Echinocyphis from the Grey Chalk. 



Fig. 1 a. EcHiNOCYPHUs difpicilis, Ayassiz. Test, natural size. British Misftim. 



(P. IIG.) 



1 b. Ambulacral and inter-ambulacral plates, magnified four diameters, do. \}u. 



Pig. :2 a. Echinocyphus difficilis. Upper surface, magnified three diameters. The Rev. 



T. Wiltshire, F.G.S. 



2 b. „ „ Under surface, do. do. Do. 

 2 c. „ ,, Lateral view, do. do. Do. 



2 d. ,, „ Ambulacral and inter-ambulacral plates, magnified 



six times. 



Pig. 3 a. Echinocyphus mespilia, Woodward, sp. Test, natural size. (P. 119.) 



British Museum. 



3 b. „ „ Upper surface, magnified three diameters. 

 3 e. „ „ Under surface, do. do. 



3 d. „ „ Lateral view, do. do. 



3 e. „ „ Ambulacral and inter-ambulacral plates, 



magnified eight diameters. 



Fig. 4. Echinocyphus difficilis. Apical disc, magnified four times. 

 Fig. 5 a. Cyphosoma Konigi, Mantell. Young test, natural size. British Museum. 



(P. 131.) 

 5 b. ,, „ Under surface, do. Do. 



5 c. ,, ,, Lateral view, do. Do. 



5 d. ,, „ Upper tlurd of ambulacrum, magnified four 



times. 



