'B 



PLATE XXIX. 



Prom the Upper and Lower Chalk. ^ 



Fig. 1 a. Cyphosoma spatcliperum, var. The Rev. T. Wiltshire, F.G.S. (P. 141.) 

 1 h_ ^, „ Upper surface of do., magnified twice. 



1 c. „ „ Lateral view of do., do. do. 



1 cl. „ „ Areal plates and zones, do. six times. 



2 a. Cyphosoma simplex, Forbes. Royal School of Mines. (P. 143.) 



3 3. ,j „ Upper surface of test, magnified two and a 



half times. 



2 c. „ ,, Upper portion of ambidacra, do. six times. 



3 a. „ „ Another test, magnified three times. 

 S b. „ „ Radiated areolae, magnified eight times, Museum 



of the Royal School of Mines. 



