Heliolites interstincta (p. 249). 



Fig. 5. A specimen found at Much Wenlock, belonging to the Collection of Mr. 

 J. S. Bowerbank. 



ba. Portion of the surface ; natural size. 



bb. Portion of the same surface, magnified. 



be. A cast found at Applethwaite, belonging to the Collection of the Geological 

 Society of London. 



bd. A part of the same surface, magnified. 



Heliolites Murchisoni (p. 250). 



Fig. 6. Under surface of a specimen found at Wenlock Edge, belonging to the 

 Museum of Paris ; natural size. 



6a. A part of the upper surface ; natural size. 



6$. A part of the surface of a smaller specimen from Dudley, belonging to M. de 

 Verneuit; natural size. 



6c. Vertical section of the specimen figured in 6 ; somewhat magnified. 



Heliolites inordinata (p. 253). 



Fig. 7. A specimen from Robeston Walthen ; in the Collection of the Geological 

 Society of London ; natural size. 



la. Part of the same, magnified. 



